21739879075 has 6 divisors (see below), whose sum is σ = 26957450084. Its totient is φ = 17391903240.

The previous prime is 21739879067. The next prime is 21739879079. The reversal of 21739879075 is 57097893712.

It is not a de Polignac number, because 21739879075 - 2³ = 21739879067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21739879079) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 434797557 + ... + 434797606.

Almost surely, 2^21739879075 is an apocalyptic number.

21739879075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21739879075 is a deficient number, since it is larger than the sum of its proper divisors (5217571009).

21739879075 is an equidigital number, since it uses as much as digits as its factorization.

21739879075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 869595173 (or 869595168 counting only the distinct ones).

The product of its (nonzero) digits is 6667920, while the sum is 58.

The spelling of 21739879075 in words is "twenty-one billion, seven hundred thirty-nine million, eight hundred seventy-nine thousand, seventy-five".