21870516872 has 16 divisors (see below), whose sum is σ = 41302237200. Its totient is φ = 10856586960.

The previous prime is 21870516869. The next prime is 21870516911. The reversal of 21870516872 is 27861507812.

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, 9832754 + ... + 9834977.

It is an arithmetic number, because the mean of its divisors is an integer number (2581389825).

Almost surely, 2^21870516872 is an apocalyptic number.

It is an amenable number.

21870516872 is a deficient number, since it is larger than the sum of its proper divisors (19431720328).

21870516872 is a wasteful number, since it uses less digits than its factorization.

21870516872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19667876 (or 19667872 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 47.

The spelling of 21870516872 in words is "twenty-one billion, eight hundred seventy million, five hundred sixteen thousand, eight hundred seventy-two".