21168810544 has 40 divisors (see below), whose sum is σ = 47080343808. Its totient is φ = 9032370240.

The previous prime is 21168810521. The next prime is 21168810563. The reversal of 21168810544 is 44501886112.

It is a junction number, because it is equal to n+sod(n) for n = 21168810497 and 21168810506.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 390892 + ... + 441739.

Almost surely, 2^21168810544 is an apocalyptic number.

It is an amenable number.

21168810544 is an abundant number, since it is smaller than the sum of its proper divisors (25911533264).

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

21168810544 is a wasteful number, since it uses less digits than its factorization.

21168810544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832873 (or 832867 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 40.

The spelling of 21168810544 in words is "twenty-one billion, one hundred sixty-eight million, eight hundred ten thousand, five hundred forty-four".