23921990 has 32 divisors (see below), whose sum is σ = 44167680. Its totient is φ = 9326304.

The previous prime is 23921977. The next prime is 23921993. The reversal of 23921990 is 9912932.

It is a self number, because there is not a number n which added to its sum of digits gives 23921990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23921993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84389 + ... + 84671.

It is an arithmetic number, because the mean of its divisors is an integer number (1380240).

Almost surely, 2^23921990 is an apocalyptic number.

23921990 is a deficient number, since it is larger than the sum of its proper divisors (20245690).

23921990 is a wasteful number, since it uses less digits than its factorization.

23921990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 23921990 is about 4891.0111429029. The cubic root of 23921990 is about 288.1370473645.

The spelling of 23921990 in words is "twenty-three million, nine hundred twenty-one thousand, nine hundred ninety".