21216531154264 has 16 divisors (see below), whose sum is σ = 39889391004000. Its totient is φ = 10579360219872.

The previous prime is 21216531154261. The next prime is 21216531154289. The reversal of 21216531154264 is 46245113561212.

It is a self number, because there is not a number n which added to its sum of digits gives 21216531154264.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216531154261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3613166539 + ... + 3613172410.

It is an arithmetic number, because the mean of its divisors is an integer number (2493086937750).

Almost surely, 2^{21216531154264} is an apocalyptic number.

It is an amenable number.

21216531154264 is a deficient number, since it is larger than the sum of its proper divisors (18672859849736).

21216531154264 is a wasteful number, since it uses less digits than its factorization.

21216531154264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7226339322 (or 7226339318 counting only the distinct ones).

The product of its digits is 345600, while the sum is 43.

The spelling of 21216531154264 in words is "twenty-one trillion, two hundred sixteen billion, five hundred thirty-one million, one hundred fifty-four thousand, two hundred sixty-four".