21864717688 has 32 divisors (see below), whose sum is σ = 47354070960. Its totient is φ = 9353889280.

The previous prime is 21864717619. The next prime is 21864717691. The reversal of 21864717688 is 88671746812.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7306231 + ... + 7309222.

Almost surely, 2^21864717688 is an apocalyptic number.

It is an amenable number.

21864717688 is an abundant number, since it is smaller than the sum of its proper divisors (25489353272).

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

21864717688 is a wasteful number, since it uses less digits than its factorization.

21864717688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14615487 (or 14615483 counting only the distinct ones).

The product of its digits is 7225344, while the sum is 58.

The spelling of 21864717688 in words is "twenty-one billion, eight hundred sixty-four million, seven hundred seventeen thousand, six hundred eighty-eight".