21672813895 has 16 divisors (see below), whose sum is σ = 26331671520. Its totient is φ = 17123094144.

The previous prime is 21672813859. The next prime is 21672813937. The reversal of 21672813895 is 59831827612.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21672813895 - 2¹⁹ = 21672289607 is a prime.

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, 102549 + ... + 232081.

It is an arithmetic number, because the mean of its divisors is an integer number (1645729470).

Almost surely, 2^21672813895 is an apocalyptic number.

21672813895 is a deficient number, since it is larger than the sum of its proper divisors (4658857625).

21672813895 is a wasteful number, since it uses less digits than its factorization.

21672813895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129954.

The product of its digits is 1451520, while the sum is 52.

The spelling of 21672813895 in words is "twenty-one billion, six hundred seventy-two million, eight hundred thirteen thousand, eight hundred ninety-five".