23191920 has 120 divisors (see below), whose sum is σ = 80838576. Its totient is φ = 6179328.

The previous prime is 23191907. The next prime is 23191957. The reversal of 23191920 is 2919132.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 18844 + ... + 20036.

Almost surely, 2^23191920 is an apocalyptic number.

23191920 is a gapful number since it is divisible by the number (20) 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 23191920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40419288).

23191920 is an abundant number, since it is smaller than the sum of its proper divisors (57646656).

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

23191920 is a wasteful number, since it uses less digits than its factorization.

23191920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1221 (or 1203 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 23191920 is about 4815.7989991278. The cubic root of 23191920 is about 285.1755151568.

The spelling of 23191920 in words is "twenty-three million, one hundred ninety-one thousand, nine hundred twenty".