21767693816 has 24 divisors (see below), whose sum is σ = 44862139560. Its totient is φ = 9894405840.

The previous prime is 21767693807. The next prime is 21767693839. The reversal of 21767693816 is 61839676712.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11242676 + ... + 11244611.

It is an arithmetic number, because the mean of its divisors is an integer number (1869255815).

Almost surely, 2^21767693816 is an apocalyptic number.

It is an amenable number.

21767693816 is an abundant number, since it is smaller than the sum of its proper divisors (23094445744).

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

21767693816 is a wasteful number, since it uses less digits than its factorization.

21767693816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22487315 (or 22487300 counting only the distinct ones).

The product of its digits is 4572288, while the sum is 56.

The spelling of 21767693816 in words is "twenty-one billion, seven hundred sixty-seven million, six hundred ninety-three thousand, eight hundred sixteen".