23551440 has 120 divisors (see below), whose sum is σ = 80349024. Its totient is φ = 5702400.

The previous prime is 23551433. The next prime is 23551441. The reversal of 23551440 is 4415532.

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 (24).

It is a self number, because there is not a number n which added to its sum of digits gives 23551440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23551441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28635 + ... + 29445.

Almost surely, 2^23551440 is an apocalyptic number.

23551440 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 23551440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40174512).

23551440 is an abundant number, since it is smaller than the sum of its proper divisors (56797584).

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

23551440 is a wasteful number, since it uses less digits than its factorization.

23551440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849 (or 832 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 23551440 is about 4852.9825880586. The cubic root of 23551440 is about 286.6415578032.

Adding to 23551440 its reverse (4415532), we get a palindrome (27966972).

The spelling of 23551440 in words is "twenty-three million, five hundred fifty-one thousand, four hundred forty".