25858561 has 2 divisors, whose sum is σ = 25858562. Its totient is φ = 25858560.

The previous prime is 25858537. The next prime is 25858589. The reversal of 25858561 is 16585852.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25310961 + 547600 = 5031^2 + 740^2 .

It is a cyclic number.

It is not a de Polignac number, because 25858561 - 2⁵ = 25858529 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (25858531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12929280 + 12929281.

It is an arithmetic number, because the mean of its divisors is an integer number (12929281).

Almost surely, 2^25858561 is an apocalyptic number.

It is an amenable number.

25858561 is a deficient number, since it is larger than the sum of its proper divisors (1).

25858561 is an equidigital number, since it uses as much as digits as its factorization.

25858561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96000, while the sum is 40.

The square root of 25858561 is about 5085.1313650682. The cubic root of 25858561 is about 295.7114342895.

The spelling of 25858561 in words is "twenty-five million, eight hundred fifty-eight thousand, five hundred sixty-one".