22991904 has 192 divisors, whose sum is σ = 76204800. Its totient is φ = 6690816.

The previous prime is 22991869. The next prime is 22991909. The reversal of 22991904 is 40919922.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22991909) 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 31 ways as a sum of consecutive naturals, for example, 258292 + ... + 258380.

It is an arithmetic number, because the mean of its divisors is an integer number (396900).

Almost surely, 2^22991904 is an apocalyptic number.

22991904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22991904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38102400).

22991904 is an abundant number, since it is smaller than the sum of its proper divisors (53212896).

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

22991904 is a wasteful number, since it uses less digits than its factorization.

22991904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 22991904 is about 4794.9873826737. The cubic root of 22991904 is about 284.3533260300.

The spelling of 22991904 in words is "twenty-two million, nine hundred ninety-one thousand, nine hundred four".