21315113361 has 32 divisors (see below), whose sum is σ = 32698848000. Its totient is φ = 13706630784.

The previous prime is 21315113329. The next prime is 21315113377. The reversal of 21315113361 is 16331151312.

It is a happy number.

21315113361 is a `hidden beast` number, since 2 + 1 + 315 + 11 + 336 + 1 = 666.

It is not a de Polignac number, because 21315113361 - 2⁵ = 21315113329 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21315113461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 819525 + ... + 845133.

It is an arithmetic number, because the mean of its divisors is an integer number (1021839000).

Almost surely, 2^21315113361 is an apocalyptic number.

It is an amenable number.

21315113361 is a deficient number, since it is larger than the sum of its proper divisors (11383734639).

21315113361 is a wasteful number, since it uses less digits than its factorization.

21315113361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26710 (or 26704 counting only the distinct ones).

The product of its digits is 1620, while the sum is 27.

Adding to 21315113361 its reverse (16331151312), we get a palindrome (37646264673).

The spelling of 21315113361 in words is "twenty-one billion, three hundred fifteen million, one hundred thirteen thousand, three hundred sixty-one".