25736640 has 224 divisors, whose sum is σ = 92171520. Its totient is φ = 6045696.

The previous prime is 25736639. The next prime is 25736651. The reversal of 25736640 is 4663752.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 310039 + ... + 310121.

It is an arithmetic number, because the mean of its divisors is an integer number (411480).

Almost surely, 2^25736640 is an apocalyptic number.

25736640 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 25736640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46085760).

25736640 is an abundant number, since it is smaller than the sum of its proper divisors (66434880).

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

25736640 is a wasteful number, since it uses less digits than its factorization.

25736640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 33.

The square root of 25736640 is about 5073.1292118376. The cubic root of 25736640 is about 295.2459502064.

The spelling of 25736640 in words is "twenty-five million, seven hundred thirty-six thousand, six hundred forty".