25217557 has 2 divisors, whose sum is σ = 25217558. Its totient is φ = 25217556.

The previous prime is 25217537. The next prime is 25217561. The reversal of 25217557 is 75571252.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23755876 + 1461681 = 4874^2 + 1209^2 .

It is a cyclic number.

It is not a de Polignac number, because 25217557 - 2¹⁹ = 24693269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25217537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12608778 + 12608779.

It is an arithmetic number, because the mean of its divisors is an integer number (12608779).

Almost surely, 2^25217557 is an apocalyptic number.

It is an amenable number.

25217557 is a deficient number, since it is larger than the sum of its proper divisors (1).

25217557 is an equidigital number, since it uses as much as digits as its factorization.

25217557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24500, while the sum is 34.

The square root of 25217557 is about 5021.7085737824. The cubic root of 25217557 is about 293.2475126291.

The spelling of 25217557 in words is "twenty-five million, two hundred seventeen thousand, five hundred fifty-seven".