21686922844 has 12 divisors (see below), whose sum is σ = 38250951424. Its totient is φ = 10758079584.

The previous prime is 21686922811. The next prime is 21686922871. The reversal of 21686922844 is 44822968612.

It is a happy number.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21686922791 and 21686922800.

It is a congruent number.

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, 21344889 + ... + 21345904.

Almost surely, 2^21686922844 is an apocalyptic number.

It is an amenable number.

21686922844 is a deficient number, since it is larger than the sum of its proper divisors (16564028580).

21686922844 is a wasteful number, since it uses less digits than its factorization.

21686922844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42690924 (or 42690922 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 52.

The spelling of 21686922844 in words is "twenty-one billion, six hundred eighty-six million, nine hundred twenty-two thousand, eight hundred forty-four".