21422904 has 32 divisors (see below), whose sum is σ = 54240000. Its totient is φ = 7049952.

The previous prime is 21422897. The next prime is 21422939. The reversal of 21422904 is 40922412.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3754 + ... + 7545.

It is an arithmetic number, because the mean of its divisors is an integer number (1695000).

Almost surely, 2^21422904 is an apocalyptic number.

21422904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21422904 is an abundant number, since it is smaller than the sum of its proper divisors (32817096).

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

21422904 is a wasteful number, since it uses less digits than its factorization.

21422904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11387 (or 11383 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21422904 is about 4628.4883061319. The cubic root of 21422904 is about 277.7321229619.

The spelling of 21422904 in words is "twenty-one million, four hundred twenty-two thousand, nine hundred four".