21513727012 has 12 divisors (see below), whose sum is σ = 37650113676. Its totient is φ = 10756551680.

The previous prime is 21513726977. The next prime is 21513727021. The reversal of 21513727012 is 21072731512.

It can be written as a sum of positive squares in 2 ways, for example, as 10291290916 + 11222436096 = 101446^2 + 105936^2 .

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, 153888 + ... + 258280.

It is an arithmetic number, because the mean of its divisors is an integer number (3137509473).

Almost surely, 2^21513727012 is an apocalyptic number.

It is an amenable number.

21513727012 is a deficient number, since it is larger than the sum of its proper divisors (16136386664).

21513727012 is a wasteful number, since it uses less digits than its factorization.

21513727012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155918 (or 155916 counting only the distinct ones).

The product of its (nonzero) digits is 5880, while the sum is 31.

The spelling of 21513727012 in words is "twenty-one billion, five hundred thirteen million, seven hundred twenty-seven thousand, twelve".