21516727732 has 12 divisors (see below), whose sum is σ = 37800790020. Its totient is φ = 10716502016.

The previous prime is 21516727613. The next prime is 21516727751. The reversal of 21516727732 is 23772761512.

It can be written as a sum of positive squares in 2 ways, for example, as 17005724836 + 4511002896 = 130406^2 + 67164^2 .

It is a congruent number.

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, 10464307 + ... + 10466362.

It is an arithmetic number, because the mean of its divisors is an integer number (3150065835).

Almost surely, 2^21516727732 is an apocalyptic number.

It is an amenable number.

21516727732 is a deficient number, since it is larger than the sum of its proper divisors (16284062288).

21516727732 is a wasteful number, since it uses less digits than its factorization.

21516727732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20930930 (or 20930928 counting only the distinct ones).

The product of its digits is 246960, while the sum is 43.

The spelling of 21516727732 in words is "twenty-one billion, five hundred sixteen million, seven hundred twenty-seven thousand, seven hundred thirty-two".