21765662730 has 96 divisors (see below), whose sum is σ = 65586163968. Its totient is φ = 4904928000.

The previous prime is 21765662713. The next prime is 21765662741. The reversal of 21765662730 is 3726656712.

21765662730 is a `hidden beast` number, since 2 + 17 + 6 + 5 + 6 + 627 + 3 + 0 = 666.

It is a super-2 number, since 2×21765662730² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 198571 + ... + 288030.

It is an arithmetic number, because the mean of its divisors is an integer number (683189208).

Almost surely, 2^21765662730 is an apocalyptic number.

21765662730 is an abundant number, since it is smaller than the sum of its proper divisors (43820501238).

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

21765662730 is a wasteful number, since it uses less digits than its factorization.

21765662730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 486692 (or 486689 counting only the distinct ones).

The product of its (nonzero) digits is 635040, while the sum is 45.

The spelling of 21765662730 in words is "twenty-one billion, seven hundred sixty-five million, six hundred sixty-two thousand, seven hundred thirty".