21271892 has 12 divisors (see below), whose sum is σ = 38232180. Its totient is φ = 10348416.

The previous prime is 21271891. The next prime is 21271903. The reversal of 21271892 is 29817212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19749136 + 1522756 = 4444^2 + 1234^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21271891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71717 + ... + 72012.

It is an arithmetic number, because the mean of its divisors is an integer number (3186015).

Almost surely, 2^21271892 is an apocalyptic number.

It is an amenable number.

21271892 is a deficient number, since it is larger than the sum of its proper divisors (16960288).

21271892 is a wasteful number, since it uses less digits than its factorization.

21271892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143770 (or 143768 counting only the distinct ones).

The product of its digits is 4032, while the sum is 32.

The square root of 21271892 is about 4612.1461381877. The cubic root of 21271892 is about 277.0779972113.

The spelling of 21271892 in words is "twenty-one million, two hundred seventy-one thousand, eight hundred ninety-two".