25251265181 has 2 divisors, whose sum is σ = 25251265182. Its totient is φ = 25251265180.

The previous prime is 25251265177. The next prime is 25251265189. The reversal of 25251265181 is 18156215252.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22151559556 + 3099705625 = 148834^2 + 55675^2 .

It is a cyclic number.

It is not a de Polignac number, because 25251265181 - 2² = 25251265177 is a prime.

It is a super-2 number, since 2×25251265181² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25251265189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12625632590 + 12625632591.

It is an arithmetic number, because the mean of its divisors is an integer number (12625632591).

Almost surely, 2^25251265181 is an apocalyptic number.

It is an amenable number.

25251265181 is a deficient number, since it is larger than the sum of its proper divisors (1).

25251265181 is an equidigital number, since it uses as much as digits as its factorization.

25251265181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48000, while the sum is 38.

The spelling of 25251265181 in words is "twenty-five billion, two hundred fifty-one million, two hundred sixty-five thousand, one hundred eighty-one".