21519168974 has 4 divisors (see below), whose sum is σ = 32278753464. Its totient is φ = 10759584486.

The previous prime is 21519168917. The next prime is 21519169027. The reversal of 21519168974 is 47986191512.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5379792242 + ... + 5379792245.

It is an arithmetic number, because the mean of its divisors is an integer number (8069688366).

Almost surely, 2^21519168974 is an apocalyptic number.

21519168974 is a deficient number, since it is larger than the sum of its proper divisors (10759584490).

21519168974 is a wasteful number, since it uses less digits than its factorization.

21519168974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10759584489.

The product of its digits is 1088640, while the sum is 53.

The spelling of 21519168974 in words is "twenty-one billion, five hundred nineteen million, one hundred sixty-eight thousand, nine hundred seventy-four".