21500360516 has 6 divisors (see below), whose sum is σ = 37625630910. Its totient is φ = 10750180256.

The previous prime is 21500360503. The next prime is 21500360549. The reversal of 21500360516 is 61506300512.

It can be written as a sum of positive squares in only one way, i.e., 14891320900 + 6609039616 = 122030^2 + 81296^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2687545061 + ... + 2687545068.

It is an arithmetic number, because the mean of its divisors is an integer number (6270938485).

Almost surely, 2^21500360516 is an apocalyptic number.

It is an amenable number.

21500360516 is a deficient number, since it is larger than the sum of its proper divisors (16125270394).

21500360516 is a wasteful number, since it uses less digits than its factorization.

21500360516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5375090133 (or 5375090131 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 29.

The spelling of 21500360516 in words is "twenty-one billion, five hundred million, three hundred sixty thousand, five hundred sixteen".