21938793 has 8 divisors (see below), whose sum is σ = 30195456. Its totient is φ = 14154000.

The previous prime is 21938779. The next prime is 21938831. The reversal of 21938793 is 39783912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21938793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21938713) 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, 117858 + ... + 118043.

It is an arithmetic number, because the mean of its divisors is an integer number (3774432).

Almost surely, 2^21938793 is an apocalyptic number.

It is an amenable number.

21938793 is a deficient number, since it is larger than the sum of its proper divisors (8256663).

21938793 is a wasteful number, since it uses less digits than its factorization.

21938793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235935.

The product of its digits is 81648, while the sum is 42.

The square root of 21938793 is about 4683.8865272336. The cubic root of 21938793 is about 279.9438365244.

The spelling of 21938793 in words is "twenty-one million, nine hundred thirty-eight thousand, seven hundred ninety-three".