25099961 has 2 divisors, whose sum is σ = 25099962. Its totient is φ = 25099960.

The previous prime is 25099903. The next prime is 25099999. The reversal of 25099961 is 16999052.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16362025 + 8737936 = 4045^2 + 2956^2 .

It is a cyclic number.

It is not a de Polignac number, because 25099961 - 2¹⁸ = 24837817 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (25099561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12549980 + 12549981.

It is an arithmetic number, because the mean of its divisors is an integer number (12549981).

Almost surely, 2^25099961 is an apocalyptic number.

It is an amenable number.

25099961 is a deficient number, since it is larger than the sum of its proper divisors (1).

25099961 is an equidigital number, since it uses as much as digits as its factorization.

25099961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43740, while the sum is 41.

The square root of 25099961 is about 5009.9861277253. The cubic root of 25099961 is about 292.7909725349.

The spelling of 25099961 in words is "twenty-five million, ninety-nine thousand, nine hundred sixty-one".