21392271 has 12 divisors (see below), whose sum is σ = 32526520. Its totient is φ = 13510800.

The previous prime is 21392251. The next prime is 21392281. The reversal of 21392271 is 17229312.

21392271 is a `hidden beast` number, since 2 + 1 + 392 + 271 = 666.

It is not a de Polignac number, because 21392271 - 2¹⁹ = 20867983 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 (21392221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62380 + ... + 62721.

Almost surely, 2^21392271 is an apocalyptic number.

21392271 is a deficient number, since it is larger than the sum of its proper divisors (11134249).

21392271 is a wasteful number, since it uses less digits than its factorization.

21392271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125126 (or 125123 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 21392271 is about 4625.1779425229. The cubic root of 21392271 is about 277.5996817441.

The spelling of 21392271 in words is "twenty-one million, three hundred ninety-two thousand, two hundred seventy-one".