21273992 has 16 divisors (see below), whose sum is σ = 40817040. Its totient is φ = 10389456.

The previous prime is 21273991. The next prime is 21273997. The reversal of 21273992 is 29937212.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21273991) 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, 30578 + ... + 31265.

It is an arithmetic number, because the mean of its divisors is an integer number (2551065).

Almost surely, 2^21273992 is an apocalyptic number.

It is an amenable number.

21273992 is a deficient number, since it is larger than the sum of its proper divisors (19543048).

21273992 is a wasteful number, since it uses less digits than its factorization.

21273992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61892 (or 61888 counting only the distinct ones).

The product of its digits is 13608, while the sum is 35.

The square root of 21273992 is about 4612.3737923113. The cubic root of 21273992 is about 277.0871147931.

The spelling of 21273992 in words is "twenty-one million, two hundred seventy-three thousand, nine hundred ninety-two".