21893940816 has 80 divisors (see below), whose sum is σ = 63013966848. Its totient is φ = 6493360000.

The previous prime is 21893940793. The next prime is 21893940821. The reversal of 21893940816 is 61804939812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 416310 + ... + 465941.

Almost surely, 2^21893940816 is an apocalyptic number.

It is an amenable number.

21893940816 is an abundant number, since it is smaller than the sum of its proper divisors (41120026032).

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

21893940816 is a wasteful number, since it uses less digits than its factorization.

21893940816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 882320 (or 882314 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 51.

The spelling of 21893940816 in words is "twenty-one billion, eight hundred ninety-three million, nine hundred forty thousand, eight hundred sixteen".