21293790 has 32 divisors (see below), whose sum is σ = 58406400. Its totient is φ = 4867104.

The previous prime is 21293777. The next prime is 21293803. The reversal of 21293790 is 9739212.

It is an interprime number because it is at equal distance from previous prime (21293777) and next prime (21293803).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50490 + ... + 50909.

It is an arithmetic number, because the mean of its divisors is an integer number (1825200).

Almost surely, 2^21293790 is an apocalyptic number.

21293790 is an abundant number, since it is smaller than the sum of its proper divisors (37112610).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21293790 is a wasteful number, since it uses less digits than its factorization.

21293790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101416.

The product of its (nonzero) digits is 6804, while the sum is 33.

The square root of 21293790 is about 4614.5194766086. The cubic root of 21293790 is about 277.1730424030.

The spelling of 21293790 in words is "twenty-one million, two hundred ninety-three thousand, seven hundred ninety".