25565620 has 24 divisors (see below), whose sum is σ = 56846664. Its totient is φ = 9624576.

The previous prime is 25565597. The next prime is 25565641. The reversal of 25565620 is 2656552.

It can be written as a sum of positive squares in 4 ways, for example, as 4276624 + 21288996 = 2068^2 + 4614^2 .

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 7 ways as a sum of consecutive naturals, for example, 37257 + ... + 37936.

It is an arithmetic number, because the mean of its divisors is an integer number (2368611).

Almost surely, 2^25565620 is an apocalyptic number.

25565620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25565620 is an abundant number, since it is smaller than the sum of its proper divisors (31281044).

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

25565620 is a wasteful number, since it uses less digits than its factorization.

25565620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75219 (or 75217 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 25565620 is about 5056.2456427670. The cubic root of 25565620 is about 294.5905264078.

The spelling of 25565620 in words is "twenty-five million, five hundred sixty-five thousand, six hundred twenty".