25118981 has 2 divisors, whose sum is σ = 25118982. Its totient is φ = 25118980.

The previous prime is 25118963. The next prime is 25118993. The reversal of 25118981 is 18981152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25090081 + 28900 = 5009^2 + 170^2 .

It is a cyclic number.

It is not a de Polignac number, because 25118981 - 2¹⁰ = 25117957 is a prime.

It is a super-2 number, since 2×25118981² = 1261926412956722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25118081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12559490 + 12559491.

It is an arithmetic number, because the mean of its divisors is an integer number (12559491).

Almost surely, 2^25118981 is an apocalyptic number.

It is an amenable number.

25118981 is a deficient number, since it is larger than the sum of its proper divisors (1).

25118981 is an equidigital number, since it uses as much as digits as its factorization.

25118981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 35.

The square root of 25118981 is about 5011.8839771088. The cubic root of 25118981 is about 292.8649099439.

The spelling of 25118981 in words is "twenty-five million, one hundred eighteen thousand, nine hundred eighty-one".