25403640 has 64 divisors (see below), whose sum is σ = 76809600. Its totient is φ = 6721152.

The previous prime is 25403563. The next prime is 25403671. The reversal of 25403640 is 4630452.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 25403640.

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 15 ways as a sum of consecutive naturals, for example, 15919 + ... + 17441.

It is an arithmetic number, because the mean of its divisors is an integer number (1200150).

Almost surely, 2^25403640 is an apocalyptic number.

25403640 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 25403640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38404800).

25403640 is an abundant number, since it is smaller than the sum of its proper divisors (51405960).

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

25403640 is a wasteful number, since it uses less digits than its factorization.

25403640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1676 (or 1672 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 24.

The square root of 25403640 is about 5040.2023768892. The cubic root of 25403640 is about 293.9670470725.

The spelling of 25403640 in words is "twenty-five million, four hundred three thousand, six hundred forty".