25181551 has 2 divisors, whose sum is σ = 25181552. Its totient is φ = 25181550.

The previous prime is 25181549. The next prime is 25181581. The reversal of 25181551 is 15518152.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25181551 - 2¹ = 25181549 is a prime.

It is a super-2 number, since 2×25181551² = 1268221021531202, which contains 22 as substring.

Together with 25181549, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25181501) 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, 12590775 + 12590776.

It is an arithmetic number, because the mean of its divisors is an integer number (12590776).

Almost surely, 2^25181551 is an apocalyptic number.

25181551 is a deficient number, since it is larger than the sum of its proper divisors (1).

25181551 is an equidigital number, since it uses as much as digits as its factorization.

25181551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2000, while the sum is 28.

The square root of 25181551 is about 5018.1222583751. The cubic root of 25181551 is about 293.1078784422.

The spelling of 25181551 in words is "twenty-five million, one hundred eighty-one thousand, five hundred fifty-one".