25291220 has 12 divisors (see below), whose sum is σ = 53111604. Its totient is φ = 10116480.

The previous prime is 25291213. The next prime is 25291241. The reversal of 25291220 is 2219252.

It can be written as a sum of positive squares in 2 ways, for example, as 14961424 + 10329796 = 3868^2 + 3214^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 632261 + ... + 632300.

It is an arithmetic number, because the mean of its divisors is an integer number (4425967).

Almost surely, 2^25291220 is an apocalyptic number.

25291220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25291220 is an abundant number, since it is smaller than the sum of its proper divisors (27820384).

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

25291220 is a wasteful number, since it uses less digits than its factorization.

25291220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1264570 (or 1264568 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 25291220 is about 5029.0376813064. The cubic root of 25291220 is about 293.5327701347.

The spelling of 25291220 in words is "twenty-five million, two hundred ninety-one thousand, two hundred twenty".