25099661 has 2 divisors, whose sum is σ = 25099662. Its totient is φ = 25099660.

The previous prime is 25099651. The next prime is 25099681. The reversal of 25099661 is 16699052.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23222761 + 1876900 = 4819^2 + 1370^2 .

It is a cyclic number.

It is not a de Polignac number, because 25099661 - 2⁶ = 25099597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25099621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12549830 + 12549831.

It is an arithmetic number, because the mean of its divisors is an integer number (12549831).

Almost surely, 2^25099661 is an apocalyptic number.

It is an amenable number.

25099661 is a deficient number, since it is larger than the sum of its proper divisors (1).

25099661 is an equidigital number, since it uses as much as digits as its factorization.

25099661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 25099661 is about 5009.9561874332. The cubic root of 25099661 is about 292.7898060305.

The spelling of 25099661 in words is "twenty-five million, ninety-nine thousand, six hundred sixty-one".