21910838 has 16 divisors (see below), whose sum is σ = 35017920. Its totient is φ = 10252296.

The previous prime is 21910829. The next prime is 21910843. The reversal of 21910838 is 83801912.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 320 + ... + 6627.

It is an arithmetic number, because the mean of its divisors is an integer number (2188620).

Almost surely, 2^21910838 is an apocalyptic number.

21910838 is a deficient number, since it is larger than the sum of its proper divisors (13107082).

21910838 is a wasteful number, since it uses less digits than its factorization.

21910838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7051.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 21910838 is about 4680.9014089169. The cubic root of 21910838 is about 279.8248819969.

The spelling of 21910838 in words is "twenty-one million, nine hundred ten thousand, eight hundred thirty-eight".