25520621 has 12 divisors (see below), whose sum is σ = 31434588. Its totient is φ = 20587392.

The previous prime is 25520617. The next prime is 25520623. The reversal of 25520621 is 12602552.

It can be written as a sum of positive squares in 2 ways, for example, as 22458121 + 3062500 = 4739^2 + 1750^2 .

It is not a de Polignac number, because 25520621 - 2² = 25520617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25520623) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14486 + ... + 16151.

It is an arithmetic number, because the mean of its divisors is an integer number (2619549).

Almost surely, 2^25520621 is an apocalyptic number.

It is an amenable number.

25520621 is a deficient number, since it is larger than the sum of its proper divisors (5913967).

25520621 is a wasteful number, since it uses less digits than its factorization.

25520621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30668 (or 30661 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 25520621 is about 5051.7938398157. The cubic root of 25520621 is about 294.4175849819.

The spelling of 25520621 in words is "twenty-five million, five hundred twenty thousand, six hundred twenty-one".