21321172316 has 48 divisors (see below), whose sum is σ = 41389608960. Its totient is φ = 9564667200.

The previous prime is 21321172253. The next prime is 21321172321. The reversal of 21321172316 is 61327112312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116165 + ... + 236931.

It is an arithmetic number, because the mean of its divisors is an integer number (862283520).

Almost surely, 2^21321172316 is an apocalyptic number.

It is an amenable number.

21321172316 is a deficient number, since it is larger than the sum of its proper divisors (20068436644).

21321172316 is a wasteful number, since it uses less digits than its factorization.

21321172316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120914 (or 120912 counting only the distinct ones).

The product of its digits is 3024, while the sum is 29.

Adding to 21321172316 its reverse (61327112312), we get a palindrome (82648284628).

The spelling of 21321172316 in words is "twenty-one billion, three hundred twenty-one million, one hundred seventy-two thousand, three hundred sixteen".