21727122717 has 16 divisors (see below), whose sum is σ = 29269735040. Its totient is φ = 14334812352.

The previous prime is 21727122701. The next prime is 21727122733. The reversal of 21727122717 is 71722172712.

It is an interprime number because it is at equal distance from previous prime (21727122701) and next prime (21727122733).

It is not a de Polignac number, because 21727122717 - 2⁴ = 21727122701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21727122757) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 471459 + ... + 515487.

It is an arithmetic number, because the mean of its divisors is an integer number (1829358440).

Almost surely, 2^21727122717 is an apocalyptic number.

It is an amenable number.

21727122717 is a deficient number, since it is larger than the sum of its proper divisors (7542612323).

21727122717 is a wasteful number, since it uses less digits than its factorization.

21727122717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45732.

The product of its digits is 38416, while the sum is 39.

The spelling of 21727122717 in words is "twenty-one billion, seven hundred twenty-seven million, one hundred twenty-two thousand, seven hundred seventeen".