25097221 has 2 divisors, whose sum is σ = 25097222. Its totient is φ = 25097220.

The previous prime is 25097213. The next prime is 25097227. The reversal of 25097221 is 12279052.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21996100 + 3101121 = 4690^2 + 1761^2 .

It is a cyclic number.

It is not a de Polignac number, because 25097221 - 2³ = 25097213 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25097221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25097227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12548610 + 12548611.

It is an arithmetic number, because the mean of its divisors is an integer number (12548611).

Almost surely, 2^25097221 is an apocalyptic number.

It is an amenable number.

25097221 is a deficient number, since it is larger than the sum of its proper divisors (1).

25097221 is an equidigital number, since it uses as much as digits as its factorization.

25097221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 25097221 is about 5009.7126664111. The cubic root of 25097221 is about 292.7803181165.

It can be divided in two parts, 2509 and 7221, that added together give a triangular number (9730 = T₁₃₉).

The spelling of 25097221 in words is "twenty-five million, ninety-seven thousand, two hundred twenty-one".