25421981157 has 12 divisors (see below), whose sum is σ = 36777934284. Its totient is φ = 16921543680.

The previous prime is 25421981147. The next prime is 25421981227. The reversal of 25421981157 is 75118912452.

25421981157 is a `hidden beast` number, since 2 + 542 + 1 + 98 + 1 + 15 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 22117340961 + 3304640196 = 148719^2 + 57486^2 .

It is not a de Polignac number, because 25421981157 - 2¹¹ = 25421979109 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25421981147) 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 in 11 ways as a sum of consecutive naturals, for example, 2197558 + ... + 2209095.

It is an arithmetic number, because the mean of its divisors is an integer number (3064827857).

Almost surely, 2^25421981157 is an apocalyptic number.

It is an amenable number.

25421981157 is a deficient number, since it is larger than the sum of its proper divisors (11355953127).

25421981157 is a wasteful number, since it uses less digits than its factorization.

25421981157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4407300 (or 4407297 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The spelling of 25421981157 in words is "twenty-five billion, four hundred twenty-one million, nine hundred eighty-one thousand, one hundred fifty-seven".