25641820 has 24 divisors (see below), whose sum is σ = 54532800. Its totient is φ = 10126272.

The previous prime is 25641793. The next prime is 25641821. The reversal of 25641820 is 2814652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25641821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6535 + ... + 9694.

It is an arithmetic number, because the mean of its divisors is an integer number (2272200).

Almost surely, 2^25641820 is an apocalyptic number.

25641820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25641820 is an abundant number, since it is smaller than the sum of its proper divisors (28890980).

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

25641820 is a wasteful number, since it uses less digits than its factorization.

25641820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16317 (or 16315 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 25641820 is about 5063.7752714748. The cubic root of 25641820 is about 294.8829182032.

The spelling of 25641820 in words is "twenty-five million, six hundred forty-one thousand, eight hundred twenty".