21655314523 has 16 divisors (see below), whose sum is σ = 22910872320. Its totient is φ = 20435097600.

The previous prime is 21655314517. The next prime is 21655314547. The reversal of 21655314523 is 32541355612.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21655314523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21655314503) 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, 3694411 + ... + 3700267.

It is an arithmetic number, because the mean of its divisors is an integer number (1431929520).

Almost surely, 2^21655314523 is an apocalyptic number.

21655314523 is a deficient number, since it is larger than the sum of its proper divisors (1255557797).

21655314523 is a wasteful number, since it uses less digits than its factorization.

21655314523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8838.

The product of its digits is 108000, while the sum is 37.

The spelling of 21655314523 in words is "twenty-one billion, six hundred fifty-five million, three hundred fourteen thousand, five hundred twenty-three".