25651840 has 64 divisors (see below), whose sum is σ = 61965000. Its totient is φ = 10153984.

The previous prime is 25651837. The next prime is 25651883. The reversal of 25651840 is 4815652.

It can be written as a sum of positive squares in 4 ways, for example, as 8809024 + 16842816 = 2968^2 + 4104^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95226 + ... + 95494.

Almost surely, 2^25651840 is an apocalyptic number.

25651840 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 25651840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30982500).

25651840 is an abundant number, since it is smaller than the sum of its proper divisors (36313160).

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

25651840 is a wasteful number, since it uses less digits than its factorization.

25651840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437 (or 425 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 25651840 is about 5064.7645552385. The cubic root of 25651840 is about 294.9213234601.

The spelling of 25651840 in words is "twenty-five million, six hundred fifty-one thousand, eight hundred forty".