25629221 has 2 divisors, whose sum is σ = 25629222. Its totient is φ = 25629220.

The previous prime is 25629209. The next prime is 25629229. The reversal of 25629221 is 12292652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19936225 + 5692996 = 4465^2 + 2386^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25629221 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a pancake number, because a pancake can be divided into 25629221 parts by 7159 straight cuts.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25629229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12814610 + 12814611.

It is an arithmetic number, because the mean of its divisors is an integer number (12814611).

Almost surely, 2^25629221 is an apocalyptic number.

It is an amenable number.

25629221 is a deficient number, since it is larger than the sum of its proper divisors (1).

25629221 is an equidigital number, since it uses as much as digits as its factorization.

25629221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 29.

The square root of 25629221 is about 5062.5310863243. The cubic root of 25629221 is about 294.8346137986.

The spelling of 25629221 in words is "twenty-five million, six hundred twenty-nine thousand, two hundred twenty-one".