21727444671 has 16 divisors (see below), whose sum is σ = 32193907200. Its totient is φ = 14482668024.

The previous prime is 21727444663. The next prime is 21727444681. The reversal of 21727444671 is 17644472712.

21727444671 is a `hidden beast` number, since 2 + 1 + 72 + 74 + 446 + 71 = 666.

It is not a de Polignac number, because 21727444671 - 2³ = 21727444663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21727444631) 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, 119370 + ... + 240216.

It is an arithmetic number, because the mean of its divisors is an integer number (2012119200).

Almost surely, 2^21727444671 is an apocalyptic number.

21727444671 is a deficient number, since it is larger than the sum of its proper divisors (10466462529).

21727444671 is a wasteful number, since it uses less digits than its factorization.

21727444671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127515 (or 127509 counting only the distinct ones).

The product of its digits is 526848, while the sum is 45.

The spelling of 21727444671 in words is "twenty-one billion, seven hundred twenty-seven million, four hundred forty-four thousand, six hundred seventy-one".