1278142536 has 64 divisors (see below), whose sum is σ = 3500481600. Its totient is φ = 385689600.

The previous prime is 1278142531. The next prime is 1278142571. The reversal of 1278142536 is 6352418721.

It is a super-2 number, since 2×1278142536² = 3267296684665022592, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1278142494 and 1278142503.

It is not an unprimeable number, because it can be changed into a prime (1278142531) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 53580 + ... + 73668.

It is an arithmetic number, because the mean of its divisors is an integer number (54695025).

Almost surely, 2^1278142536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1278142536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1750240800).

1278142536 is an abundant number, since it is smaller than the sum of its proper divisors (2222339064).

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

1278142536 is a wasteful number, since it uses less digits than its factorization.

1278142536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20350 (or 20346 counting only the distinct ones).

The product of its digits is 80640, while the sum is 39.

The square root of 1278142536 is about 35751.1193670912. The cubic root of 1278142536 is about 1085.2415910308.

The spelling of 1278142536 in words is "one billion, two hundred seventy-eight million, one hundred forty-two thousand, five hundred thirty-six".