25215131989 has 2 divisors, whose sum is σ = 25215131990. Its totient is φ = 25215131988.

The previous prime is 25215131983. The next prime is 25215131999. The reversal of 25215131989 is 98913151252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24678839025 + 536292964 = 157095^2 + 23158^2 .

It is a cyclic number.

It is not a de Polignac number, because 25215131989 - 2¹³ = 25215123797 is a prime.

It is a super-2 number, since 2×25215131989² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25215131983) 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, 12607565994 + 12607565995.

It is an arithmetic number, because the mean of its divisors is an integer number (12607565995).

Almost surely, 2^25215131989 is an apocalyptic number.

It is an amenable number.

25215131989 is a deficient number, since it is larger than the sum of its proper divisors (1).

25215131989 is an equidigital number, since it uses as much as digits as its factorization.

25215131989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 194400, while the sum is 46.

The spelling of 25215131989 in words is "twenty-five billion, two hundred fifteen million, one hundred thirty-one thousand, nine hundred eighty-nine".