21935290 has 32 divisors (see below), whose sum is σ = 43900416. Its totient is φ = 7836480.

The previous prime is 21935279. The next prime is 21935293. The reversal of 21935290 is 9253912.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (21935293) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1309 + ... + 6751.

It is an arithmetic number, because the mean of its divisors is an integer number (1371888).

Almost surely, 2^21935290 is an apocalyptic number.

21935290 is an abundant number, since it is smaller than the sum of its proper divisors (21965126).

21935290 is a wasteful number, since it uses less digits than its factorization.

21935290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5494.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 21935290 is about 4683.5125707102. The cubic root of 21935290 is about 279.9289360471.

The spelling of 21935290 in words is "twenty-one million, nine hundred thirty-five thousand, two hundred ninety".