25555920 has 80 divisors (see below), whose sum is σ = 85327872. Its totient is φ = 6289920.

The previous prime is 25555919. The next prime is 25555927. The reversal of 25555920 is 2955552.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25555927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 976 + ... + 7215.

Almost surely, 2^25555920 is an apocalyptic number.

25555920 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 25555920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42663936).

25555920 is an abundant number, since it is smaller than the sum of its proper divisors (59771952).

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

25555920 is a wasteful number, since it uses less digits than its factorization.

25555920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8220 (or 8214 counting only the distinct ones).

The product of its (nonzero) digits is 22500, while the sum is 33.

The square root of 25555920 is about 5055.2863420384. The cubic root of 25555920 is about 294.5532642620.

The spelling of 25555920 in words is "twenty-five million, five hundred fifty-five thousand, nine hundred twenty".