21310015321 has 16 divisors (see below), whose sum is σ = 25846801920. Its totient is φ = 17151344640.

The previous prime is 21310015297. The next prime is 21310015367. The reversal of 21310015321 is 12351001312.

It is a cyclic number.

It is not a de Polignac number, because 21310015321 - 2⁵ = 21310015289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21310018321) 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, 156456 + ... + 259033.

It is an arithmetic number, because the mean of its divisors is an integer number (1615425120).

Almost surely, 2^21310015321 is an apocalyptic number.

It is an amenable number.

21310015321 is a deficient number, since it is larger than the sum of its proper divisors (4536786599).

21310015321 is a wasteful number, since it uses less digits than its factorization.

21310015321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415944.

The product of its (nonzero) digits is 180, while the sum is 19.

Adding to 21310015321 its reverse (12351001312), we get a palindrome (33661016633).

The spelling of 21310015321 in words is "twenty-one billion, three hundred ten million, fifteen thousand, three hundred twenty-one".