21672738513 has 20 divisors (see below), whose sum is σ = 32517975600. Its totient is φ = 14384830392.

The previous prime is 21672738491. The next prime is 21672738523. The reversal of 21672738513 is 31583727612.

21672738513 is a `hidden beast` number, since 2 + 1 + 67 + 2 + 73 + 8 + 513 = 666.

It is not a de Polignac number, because 21672738513 - 2¹⁴ = 21672722129 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21672738523) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 570963 + ... + 607736.

It is an arithmetic number, because the mean of its divisors is an integer number (1625898780).

Almost surely, 2^21672738513 is an apocalyptic number.

It is an amenable number.

21672738513 is a deficient number, since it is larger than the sum of its proper divisors (10845237087).

21672738513 is a wasteful number, since it uses less digits than its factorization.

21672738513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178938 (or 1178929 counting only the distinct ones).

The product of its digits is 423360, while the sum is 45.

The spelling of 21672738513 in words is "twenty-one billion, six hundred seventy-two million, seven hundred thirty-eight thousand, five hundred thirteen".