21331761508 has 12 divisors (see below), whose sum is σ = 37539134640. Its totient is φ = 10606294472.

The previous prime is 21331761487. The next prime is 21331761523. The reversal of 21331761508 is 80516713312.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14895766 + ... + 14897197.

It is an arithmetic number, because the mean of its divisors is an integer number (3128261220).

Almost surely, 2^21331761508 is an apocalyptic number.

It is an amenable number.

21331761508 is a deficient number, since it is larger than the sum of its proper divisors (16207373132).

21331761508 is a wasteful number, since it uses less digits than its factorization.

21331761508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29793146 (or 29793144 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 37.

The spelling of 21331761508 in words is "twenty-one billion, three hundred thirty-one million, seven hundred sixty-one thousand, five hundred eight".