21103313121 has 12 divisors (see below), whose sum is σ = 33253705680. Its totient is φ = 12789886680.

The previous prime is 21103313111. The next prime is 21103313159. The reversal of 21103313121 is 12131330112.

21103313121 is a `hidden beast` number, since 21 + 1 + 0 + 331 + 312 + 1 = 666.

It is not a de Polignac number, because 21103313121 - 2⁶ = 21103313057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21103313094 and 21103313103.

It is not an unprimeable number, because it can be changed into a prime (21103313111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 106582291 + ... + 106582488.

It is an arithmetic number, because the mean of its divisors is an integer number (2771142140).

Almost surely, 2^21103313121 is an apocalyptic number.

It is an amenable number.

21103313121 is a deficient number, since it is larger than the sum of its proper divisors (12150392559).

21103313121 is a wasteful number, since it uses less digits than its factorization.

21103313121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213164796 (or 213164793 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21103313121 its reverse (12131330112), we get a palindrome (33234643233).

The spelling of 21103313121 in words is "twenty-one billion, one hundred three million, three hundred thirteen thousand, one hundred twenty-one".