1276321428 has 96 divisors (see below), whose sum is σ = 3634713600. Its totient is φ = 385510752.

The previous prime is 1276321411. The next prime is 1276321457. The reversal of 1276321428 is 8241236721.

It is a happy number.

1276321428 is a `hidden beast` number, since 1 + 2 + 7 + 632 + 14 + 2 + 8 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1276321392 and 1276321401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33675 + ... + 60717.

It is an arithmetic number, because the mean of its divisors is an integer number (37861600).

Almost surely, 2^1276321428 is an apocalyptic number.

1276321428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1276321428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1817356800).

1276321428 is an abundant number, since it is smaller than the sum of its proper divisors (2358392172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1276321428 is a wasteful number, since it uses less digits than its factorization.

1276321428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27098 (or 27090 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 1276321428 is about 35725.6410439337. The cubic root of 1276321428 is about 1084.7259256629.

It can be divided in two parts, 12763 and 21428, that added together give a triangular number (34191 = T₂₆₁).

The spelling of 1276321428 in words is "one billion, two hundred seventy-six million, three hundred twenty-one thousand, four hundred twenty-eight".