21139792 has 40 divisors (see below), whose sum is σ = 42325416. Its totient is φ = 10223616.

The previous prime is 21139777. The next prime is 21139793. The reversal of 21139792 is 29793112.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11128896 + 10010896 = 3336^2 + 3164^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21139793) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82128 + ... + 82384.

Almost surely, 2^21139792 is an apocalyptic number.

It is an amenable number.

21139792 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

21139792 is a wasteful number, since it uses less digits than its factorization.

21139792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415 (or 409 counting only the distinct ones).

The product of its digits is 6804, while the sum is 34.

The square root of 21139792 is about 4597.8029535855. The cubic root of 21139792 is about 276.5032476317.

The spelling of 21139792 in words is "twenty-one million, one hundred thirty-nine thousand, seven hundred ninety-two".