21146531306121 has 24 divisors (see below), whose sum is σ = 32894772597960. Its totient is φ = 13013183437056.

The previous prime is 21146531306113. The next prime is 21146531306123. The reversal of 21146531306121 is 12160313564112.

21146531306121 is a `hidden beast` number, since 2 + 1 + 1 + 4 + 6 + 5 + 3 + 1 + 30 + 612 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 25052558400 + 21121478747721 = 158280^2 + 4595811^2 .

It is not a de Polignac number, because 21146531306121 - 2³ = 21146531306113 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21146531306123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32485575 + ... + 33130131.

It is an arithmetic number, because the mean of its divisors is an integer number (1370615524915).

Almost surely, 2^{21146531306121} is an apocalyptic number.

It is an amenable number.

21146531306121 is a deficient number, since it is larger than the sum of its proper divisors (11748241291839).

21146531306121 is a wasteful number, since it uses less digits than its factorization.

21146531306121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 924985 (or 924982 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 21146531306121 in words is "twenty-one trillion, one hundred forty-six billion, five hundred thirty-one million, three hundred six thousand, one hundred twenty-one".