25991151021 has 48 divisors (see below), whose sum is σ = 42355541760. Its totient is φ = 15740524800.

The previous prime is 25991150993. The next prime is 25991151031. The reversal of 25991151021 is 12015119952.

25991151021 is a `hidden beast` number, since 2 + 59 + 91 + 1 + 510 + 2 + 1 = 666.

It is not a de Polignac number, because 25991151021 - 2⁹ = 25991150509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25991151031) 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 47 ways as a sum of consecutive naturals, for example, 6796716 + ... + 6800538.

It is an arithmetic number, because the mean of its divisors is an integer number (882407120).

Almost surely, 2^25991151021 is an apocalyptic number.

It is an amenable number.

25991151021 is a deficient number, since it is larger than the sum of its proper divisors (16364390739).

25991151021 is a wasteful number, since it uses less digits than its factorization.

25991151021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5935 (or 5918 counting only the distinct ones).

The product of its (nonzero) digits is 8100, while the sum is 36.

The spelling of 25991151021 in words is "twenty-five billion, nine hundred ninety-one million, one hundred fifty-one thousand, twenty-one".