21799869516 has 18 divisors (see below), whose sum is σ = 55105225812. Its totient is φ = 7266623160.

The previous prime is 21799869493. The next prime is 21799869551. The reversal of 21799869516 is 61596899712.

21799869516 is a `hidden beast` number, since 21 + 7 + 9 + 98 + 6 + 9 + 516 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 302775930 + ... + 302776001.

It is an arithmetic number, because the mean of its divisors is an integer number (3061401434).

Almost surely, 2^21799869516 is an apocalyptic number.

It is an amenable number.

21799869516 is an abundant number, since it is smaller than the sum of its proper divisors (33305356296).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21799869516 is a wasteful number, since it uses less digits than its factorization.

21799869516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 605551941 (or 605551936 counting only the distinct ones).

The product of its digits is 14696640, while the sum is 63.

The spelling of 21799869516 in words is "twenty-one billion, seven hundred ninety-nine million, eight hundred sixty-nine thousand, five hundred sixteen".