21312012113 has 16 divisors (see below), whose sum is σ = 24695537664. Its totient is φ = 18014950800.

The previous prime is 21312012077. The next prime is 21312012119. The reversal of 21312012113 is 31121021312.

It is not a de Polignac number, because 21312012113 - 2⁶ = 21312012049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21312012091 and 21312012100.

It is not an unprimeable number, because it can be changed into a prime (21312012119) 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, 76688 + ... + 220238.

It is an arithmetic number, because the mean of its divisors is an integer number (1543471104).

Almost surely, 2^21312012113 is an apocalyptic number.

It is an amenable number.

21312012113 is a deficient number, since it is larger than the sum of its proper divisors (3383525551).

21312012113 is a wasteful number, since it uses less digits than its factorization.

21312012113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143852.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21312012113 its reverse (31121021312), we get a palindrome (52433033425).

The spelling of 21312012113 in words is "twenty-one billion, three hundred twelve million, twelve thousand, one hundred thirteen".