21056032115 has 4 divisors (see below), whose sum is σ = 25267238544. Its totient is φ = 16844825688.

The previous prime is 21056032099. The next prime is 21056032147. The reversal of 21056032115 is 51123065012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21056032115 - 2⁴ = 21056032099 is a prime.

It is a super-2 number, since 2×21056032115² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2105603207 + ... + 2105603216.

It is an arithmetic number, because the mean of its divisors is an integer number (6316809636).

Almost surely, 2^21056032115 is an apocalyptic number.

21056032115 is a deficient number, since it is larger than the sum of its proper divisors (4211206429).

21056032115 is an equidigital number, since it uses as much as digits as its factorization.

21056032115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4211206428.

The product of its (nonzero) digits is 1800, while the sum is 26.

Adding to 21056032115 its reverse (51123065012), we get a palindrome (72179097127).

The spelling of 21056032115 in words is "twenty-one billion, fifty-six million, thirty-two thousand, one hundred fifteen".