21693937955 has 12 divisors (see below), whose sum is σ = 26652228480. Its totient is φ = 16951534992.

The previous prime is 21693937931. The next prime is 21693937963. The reversal of 21693937955 is 55973939612.

It is not a de Polignac number, because 21693937955 - 2¹⁸ = 21693675811 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21693937894 and 21693937903.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1164035 + ... + 1182524.

It is an arithmetic number, because the mean of its divisors is an integer number (2221019040).

Almost surely, 2^21693937955 is an apocalyptic number.

21693937955 is a deficient number, since it is larger than the sum of its proper divisors (4958290525).

21693937955 is an equidigital number, since it uses as much as digits as its factorization.

21693937955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2346650 (or 2346607 counting only the distinct ones).

The product of its digits is 13778100, while the sum is 59.

The spelling of 21693937955 in words is "twenty-one billion, six hundred ninety-three million, nine hundred thirty-seven thousand, nine hundred fifty-five".