1557638256 has 40 divisors (see below), whose sum is σ = 4162657680. Its totient is φ = 501308416.

The previous prime is 1557638239. The next prime is 1557638263. The reversal of 1557638256 is 6528367551.

It is a hoax number, since the sum of its digits (48) 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 (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 558105 + ... + 560888.

It is an arithmetic number, because the mean of its divisors is an integer number (104066442).

Almost surely, 2^1557638256 is an apocalyptic number.

1557638256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1557638256 is an abundant number, since it is smaller than the sum of its proper divisors (2605019424).

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

1557638256 is a wasteful number, since it uses less digits than its factorization.

1557638256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1119033 (or 1119027 counting only the distinct ones).

The product of its digits is 1512000, while the sum is 48.

The square root of 1557638256 is about 39466.9261027509. The cubic root of 1557638256 is about 1159.1924264163.

The spelling of 1557638256 in words is "one billion, five hundred fifty-seven million, six hundred thirty-eight thousand, two hundred fifty-six".