25215840 has 192 divisors, whose sum is σ = 95256000. Its totient is φ = 6193152.

The previous prime is 25215823. The next prime is 25215859. The reversal of 25215840 is 4851252.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 55936 + ... + 56384.

It is an arithmetic number, because the mean of its divisors is an integer number (496125).

Almost surely, 2^25215840 is an apocalyptic number.

25215840 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 25215840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47628000).

25215840 is an abundant number, since it is smaller than the sum of its proper divisors (70040160).

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

25215840 is a wasteful number, since it uses less digits than its factorization.

25215840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 486 (or 472 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 25215840 is about 5021.5376131221. The cubic root of 25215840 is about 293.2408569830.

The spelling of 25215840 in words is "twenty-five million, two hundred fifteen thousand, eight hundred forty".