25515920 has 20 divisors (see below), whose sum is σ = 59324700. Its totient is φ = 10206336.

The previous prime is 25515887. The next prime is 25515923. The reversal of 25515920 is 2951552.

It can be written as a sum of positive squares in 2 ways, for example, as 10523536 + 14992384 = 3244^2 + 3872^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (25515923) 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 3 ways as a sum of consecutive naturals, for example, 159395 + ... + 159554.

It is an arithmetic number, because the mean of its divisors is an integer number (2966235).

Almost surely, 2^25515920 is an apocalyptic number.

25515920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25515920 is an abundant number, since it is smaller than the sum of its proper divisors (33808780).

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

25515920 is a wasteful number, since it uses less digits than its factorization.

25515920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318962 (or 318956 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 29.

The square root of 25515920 is about 5051.3285381175. The cubic root of 25515920 is about 294.3995062413.

The spelling of 25515920 in words is "twenty-five million, five hundred fifteen thousand, nine hundred twenty".