25264640 has 80 divisors (see below), whose sum is σ = 61871040. Its totient is φ = 9891840.

The previous prime is 25264627. The next prime is 25264663. The reversal of 25264640 is 4646252.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 181691 + ... + 181829.

It is an arithmetic number, because the mean of its divisors is an integer number (773388).

Almost surely, 2^25264640 is an apocalyptic number.

25264640 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 25264640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30935520).

25264640 is an abundant number, since it is smaller than the sum of its proper divisors (36606400).

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

25264640 is an equidigital number, since it uses as much as digits as its factorization.

25264640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 217 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 29.

The square root of 25264640 is about 5026.3943339137. The cubic root of 25264640 is about 293.4299039246.

The spelling of 25264640 in words is "twenty-five million, two hundred sixty-four thousand, six hundred forty".