21056013059 has 4 divisors (see below), whose sum is σ = 21130416216. Its totient is φ = 20981609904.

The previous prime is 21056013029. The next prime is 21056013101. The reversal of 21056013059 is 95031065012.

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 21056013059 - 2²⁴ = 21039235843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21056013029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37201154 + ... + 37201719.

It is an arithmetic number, because the mean of its divisors is an integer number (5282604054).

Almost surely, 2^21056013059 is an apocalyptic number.

21056013059 is a deficient number, since it is larger than the sum of its proper divisors (74403157).

21056013059 is an equidigital number, since it uses as much as digits as its factorization.

21056013059 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74403156.

The product of its (nonzero) digits is 8100, while the sum is 32.

The spelling of 21056013059 in words is "twenty-one billion, fifty-six million, thirteen thousand, fifty-nine".