1256993136 has 60 divisors (see below), whose sum is σ = 4020386032. Its totient is φ = 359140608.

The previous prime is 1256993117. The next prime is 1256993149. The reversal of 1256993136 is 6313996521.

It is a super-2 number, since 2×1256993136² = 3160063487902228992, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1256993091 and 1256993100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 622501 + ... + 624516.

Almost surely, 2^1256993136 is an apocalyptic number.

1256993136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1256993136 is an abundant number, since it is smaller than the sum of its proper divisors (2763392896).

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

1256993136 is a wasteful number, since it uses less digits than its factorization.

1256993136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247038 (or 1247029 counting only the distinct ones).

The product of its digits is 262440, while the sum is 45.

The square root of 1256993136 is about 35454.0990013849. The cubic root of 1256993136 is about 1079.2224444416. Note that the first 3 decimals are identical.

The spelling of 1256993136 in words is "one billion, two hundred fifty-six million, nine hundred ninety-three thousand, one hundred thirty-six".