21768542076 has 12 divisors (see below), whose sum is σ = 50793264872. Its totient is φ = 7256180688.

The previous prime is 21768542057. The next prime is 21768542083. The reversal of 21768542076 is 67024586712.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×21768542076² (a number of 21 digits) contains 22 as substring.

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, 907022575 + ... + 907022598.

Almost surely, 2^21768542076 is an apocalyptic number.

It is an amenable number.

21768542076 is an abundant number, since it is smaller than the sum of its proper divisors (29024722796).

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

21768542076 is a wasteful number, since it uses less digits than its factorization.

21768542076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1814045180 (or 1814045178 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 48.

The spelling of 21768542076 in words is "twenty-one billion, seven hundred sixty-eight million, five hundred forty-two thousand, seventy-six".