25550640 has 100 divisors (see below), whose sum is σ = 88763664. Its totient is φ = 6811776.

The previous prime is 25550627. The next prime is 25550641. The reversal of 25550640 is 4605552.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (25550641) 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 19 ways as a sum of consecutive naturals, for example, 4509 + ... + 8451.

Almost surely, 2^25550640 is an apocalyptic number.

25550640 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 25550640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44381832).

25550640 is an abundant number, since it is smaller than the sum of its proper divisors (63213024).

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

25550640 is a wasteful number, since it uses less digits than its factorization.

25550640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3968 (or 3953 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 27.

The square root of 25550640 is about 5054.7640894507. The cubic root of 25550640 is about 294.5329773989.

The spelling of 25550640 in words is "twenty-five million, five hundred fifty thousand, six hundred forty".