25555720 has 16 divisors (see below), whose sum is σ = 57500460. Its totient is φ = 10222272.

The previous prime is 25555711. The next prime is 25555729. The reversal of 25555720 is 2755552.

It is an interprime number because it is at equal distance from previous prime (25555711) and next prime (25555729).

It can be written as a sum of positive squares in 2 ways, for example, as 25421764 + 133956 = 5042^2 + 366^2 .

It is not an unprimeable number, because it can be changed into a prime (25555729) 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, 319407 + ... + 319486.

Almost surely, 2^25555720 is an apocalyptic number.

25555720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25555720 is an abundant number, since it is smaller than the sum of its proper divisors (31944740).

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

25555720 is a wasteful number, since it uses less digits than its factorization.

25555720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 638904 (or 638900 counting only the distinct ones).

The product of its (nonzero) digits is 17500, while the sum is 31.

The square root of 25555720 is about 5055.2665607265. The cubic root of 25555720 is about 294.5524958712.

The spelling of 25555720 in words is "twenty-five million, five hundred fifty-five thousand, seven hundred twenty".