21372656207 has 16 divisors (see below), whose sum is σ = 25866861120. Its totient is φ = 17239039488.

The previous prime is 21372656203. The next prime is 21372656219. The reversal of 21372656207 is 70265627312.

It is a cyclic number.

It is not a de Polignac number, because 21372656207 - 2² = 21372656203 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21372656203) 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, 1074113 + ... + 1093829.

It is an arithmetic number, because the mean of its divisors is an integer number (1616678820).

Almost surely, 2^21372656207 is an apocalyptic number.

21372656207 is a deficient number, since it is larger than the sum of its proper divisors (4494204913).

21372656207 is a wasteful number, since it uses less digits than its factorization.

21372656207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28850.

The product of its (nonzero) digits is 211680, while the sum is 41.

The spelling of 21372656207 in words is "twenty-one billion, three hundred seventy-two million, six hundred fifty-six thousand, two hundred seven".