25378640 has 40 divisors (see below), whose sum is σ = 67436160. Its totient is φ = 8701056.

The previous prime is 25378627. The next prime is 25378649. The reversal of 25378640 is 4687352.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 25378640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25378649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22100 + ... + 23219.

It is an arithmetic number, because the mean of its divisors is an integer number (1685904).

Almost surely, 2^25378640 is an apocalyptic number.

25378640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25378640 is an abundant number, since it is smaller than the sum of its proper divisors (42057520).

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

25378640 is a wasteful number, since it uses less digits than its factorization.

25378640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45339 (or 45333 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 25378640 is about 5037.7217072800. The cubic root of 25378640 is about 293.8705833597.

The spelling of 25378640 in words is "twenty-five million, three hundred seventy-eight thousand, six hundred forty".