21807996679 has 8 divisors (see below), whose sum is σ = 24962928128. Its totient is φ = 18662941080.

The previous prime is 21807996647. The next prime is 21807996701. The reversal of 21807996679 is 97669970812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21807996679 - 2⁵ = 21807996647 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21807996679.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21807996619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2464227 + ... + 2473060.

It is an arithmetic number, because the mean of its divisors is an integer number (3120366016).

Almost surely, 2^21807996679 is an apocalyptic number.

21807996679 is a deficient number, since it is larger than the sum of its proper divisors (3154931449).

21807996679 is an equidigital number, since it uses as much as digits as its factorization.

21807996679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4937925.

The product of its (nonzero) digits is 20575296, while the sum is 64.

The spelling of 21807996679 in words is "twenty-one billion, eight hundred seven million, nine hundred ninety-six thousand, six hundred seventy-nine".