21731064499 has 16 divisors (see below), whose sum is σ = 22620052224. Its totient is φ = 20860106400.

The previous prime is 21731064461. The next prime is 21731064517. The reversal of 21731064499 is 99446013712.

It is a cyclic number.

It is not a de Polignac number, because 21731064499 - 2⁷ = 21731064371 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21731064799) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 3960612 + ... + 3966094.

It is an arithmetic number, because the mean of its divisors is an integer number (1413753264).

Almost surely, 2^21731064499 is an apocalyptic number.

21731064499 is a deficient number, since it is larger than the sum of its proper divisors (888987725).

21731064499 is a wasteful number, since it uses less digits than its factorization.

21731064499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7098.

The product of its (nonzero) digits is 326592, while the sum is 46.

The spelling of 21731064499 in words is "twenty-one billion, seven hundred thirty-one million, sixty-four thousand, four hundred ninety-nine".