21356402313 has 16 divisors (see below), whose sum is σ = 29877434496. Its totient is φ = 13543326720.

The previous prime is 21356402281. The next prime is 21356402321. The reversal of 21356402313 is 31320465312.

It is not a de Polignac number, because 21356402313 - 2⁵ = 21356402281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21356402393) 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, 842520 + ... + 867497.

It is an arithmetic number, because the mean of its divisors is an integer number (1867339656).

Almost surely, 2^21356402313 is an apocalyptic number.

21356402313 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21356402313 is a deficient number, since it is larger than the sum of its proper divisors (8521032183).

21356402313 is a wasteful number, since it uses less digits than its factorization.

21356402313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1710224.

The product of its (nonzero) digits is 12960, while the sum is 30.

Adding to 21356402313 its reverse (31320465312), we get a palindrome (52676867625).

The spelling of 21356402313 in words is "twenty-one billion, three hundred fifty-six million, four hundred two thousand, three hundred thirteen".