21730764873 has 16 divisors (see below), whose sum is σ = 30560480000. Its totient is φ = 13697171280.

The previous prime is 21730764857. The next prime is 21730764883. The reversal of 21730764873 is 37846703712.

It is not a de Polignac number, because 21730764873 - 2⁴ = 21730764857 is a prime.

It is a super-2 number, since 2×21730764873² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21730764883) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 353563 + ... + 410448.

It is an arithmetic number, because the mean of its divisors is an integer number (1910030000).

Almost surely, 2^21730764873 is an apocalyptic number.

It is an amenable number.

21730764873 is a deficient number, since it is larger than the sum of its proper divisors (8829715127).

21730764873 is a wasteful number, since it uses less digits than its factorization.

21730764873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 764532.

The product of its (nonzero) digits is 1185408, while the sum is 48.

The spelling of 21730764873 in words is "twenty-one billion, seven hundred thirty million, seven hundred sixty-four thousand, eight hundred seventy-three".