21067821976 has 8 divisors (see below), whose sum is σ = 39502166220. Its totient is φ = 10533910984.

The previous prime is 21067821967. The next prime is 21067822043. The reversal of 21067821976 is 67912876012.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1316738866 + ... + 1316738881.

Almost surely, 2^21067821976 is an apocalyptic number.

It is an amenable number.

21067821976 is a deficient number, since it is larger than the sum of its proper divisors (18434344244).

21067821976 is a wasteful number, since it uses less digits than its factorization.

21067821976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2633477753 (or 2633477749 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 49.

The spelling of 21067821976 in words is "twenty-one billion, sixty-seven million, eight hundred twenty-one thousand, nine hundred seventy-six".