21099599568 has 60 divisors (see below), whose sum is σ = 59110041120. Its totient is φ = 7025997888.

The previous prime is 21099599531. The next prime is 21099599593. The reversal of 21099599568 is 86599599012.

21099599568 is a `hidden beast` number, since 2 + 10 + 9 + 9 + 59 + 9 + 568 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 67023 + ... + 216081.

It is an arithmetic number, because the mean of its divisors is an integer number (985167352).

Almost surely, 2^21099599568 is an apocalyptic number.

It is an amenable number.

21099599568 is an abundant number, since it is smaller than the sum of its proper divisors (38010441552).

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

21099599568 is a wasteful number, since it uses less digits than its factorization.

21099599568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150056 (or 150047 counting only the distinct ones).

The product of its (nonzero) digits is 15746400, while the sum is 63.

The spelling of 21099599568 in words is "twenty-one billion, ninety-nine million, five hundred ninety-nine thousand, five hundred sixty-eight".