25499640 has 64 divisors (see below), whose sum is σ = 79833600. Its totient is φ = 6503552.

The previous prime is 25499633. The next prime is 25499641. The reversal of 25499640 is 4699452.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25499641) 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 15 ways as a sum of consecutive naturals, for example, 1860 + ... + 7379.

It is an arithmetic number, because the mean of its divisors is an integer number (1247400).

Almost surely, 2^25499640 is an apocalyptic number.

25499640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25499640 is an abundant number, since it is smaller than the sum of its proper divisors (54333960).

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

25499640 is a wasteful number, since it uses less digits than its factorization.

25499640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9276 (or 9272 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 39.

The square root of 25499640 is about 5049.7168237437. The cubic root of 25499640 is about 294.3368807164.

The spelling of 25499640 in words is "twenty-five million, four hundred ninety-nine thousand, six hundred forty".