21656060657013 has 16 divisors (see below), whose sum is σ = 28901251187456. Its totient is φ = 14424125526720.

The previous prime is 21656060656999. The next prime is 21656060657029. The reversal of 21656060657013 is 31075606065612.

It is not a de Polignac number, because 21656060657013 - 2³³ = 21647470722421 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21656060657053) 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, 23971983 + ... + 24858963.

It is an arithmetic number, because the mean of its divisors is an integer number (1806328199216).

Almost surely, 2^{21656060657013} is an apocalyptic number.

It is an amenable number.

21656060657013 is a deficient number, since it is larger than the sum of its proper divisors (7245190530443).

21656060657013 is a wasteful number, since it uses less digits than its factorization.

21656060657013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 894444.

The product of its (nonzero) digits is 1360800, while the sum is 48.

The spelling of 21656060657013 in words is "twenty-one trillion, six hundred fifty-six billion, sixty million, six hundred fifty-seven thousand, thirteen".