25624221 has 16 divisors (see below), whose sum is σ = 40000128. Its totient is φ = 14284800.

The previous prime is 25624189. The next prime is 25624267. The reversal of 25624221 is 12242652.

It is a happy number.

It is not a de Polignac number, because 25624221 - 2⁵ = 25624189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25624191 and 25624200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25624271) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14020 + ... + 15741.

It is an arithmetic number, because the mean of its divisors is an integer number (2500008).

Almost surely, 2^25624221 is an apocalyptic number.

25624221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

25624221 is a deficient number, since it is larger than the sum of its proper divisors (14375907).

25624221 is a wasteful number, since it uses less digits than its factorization.

25624221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29812.

The product of its digits is 1920, while the sum is 24.

The square root of 25624221 is about 5062.0372381088. The cubic root of 25624221 is about 294.8154394749.

Adding to 25624221 its reverse (12242652), we get a palindrome (37866873).

The spelling of 25624221 in words is "twenty-five million, six hundred twenty-four thousand, two hundred twenty-one".