2156538438 has 32 divisors (see below), whose sum is σ = 4794052320. Its totient is φ = 718584480.

The previous prime is 2156538431. The next prime is 2156538457. The reversal of 2156538438 is 8348356512.

2156538438 is a `hidden beast` number, since 2 + 1 + 565 + 3 + 84 + 3 + 8 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 2156538393 and 2156538402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2156538431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 193128 + ... + 203988.

It is an arithmetic number, because the mean of its divisors is an integer number (149814135).

Almost surely, 2^2156538438 is an apocalyptic number.

2156538438 is an abundant number, since it is smaller than the sum of its proper divisors (2637513882).

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

2156538438 is a wasteful number, since it uses less digits than its factorization.

2156538438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14549 (or 14543 counting only the distinct ones).

The product of its digits is 691200, while the sum is 45.

The square root of 2156538438 is about 46438.5447446407. The cubic root of 2156538438 is about 1291.9699161810.

The spelling of 2156538438 in words is "two billion, one hundred fifty-six million, five hundred thirty-eight thousand, four hundred thirty-eight".