1277872240 has 80 divisors (see below), whose sum is σ = 3119755680. Its totient is φ = 486097920.

The previous prime is 1277872159. The next prime is 1277872259. The reversal of 1277872240 is 422787721.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 1277872193 and 1277872202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151330 + ... + 159550.

It is an arithmetic number, because the mean of its divisors is an integer number (38996946).

Almost surely, 2^1277872240 is an apocalyptic number.

1277872240 is a gapful number since it is divisible by the number (10) 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 1277872240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1559877840).

1277872240 is an abundant number, since it is smaller than the sum of its proper divisors (1841883440).

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

1277872240 is a wasteful number, since it uses less digits than its factorization.

1277872240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8330 (or 8324 counting only the distinct ones).

The product of its (nonzero) digits is 87808, while the sum is 40.

The square root of 1277872240 is about 35747.3389219394. The cubic root of 1277872240 is about 1085.1650849206.

The spelling of 1277872240 in words is "one billion, two hundred seventy-seven million, eight hundred seventy-two thousand, two hundred forty".