251161591149 has 12 divisors (see below), whose sum is σ = 414615960096. Its totient is φ = 143520909192.

The previous prime is 251161591133. The next prime is 251161591171. The reversal of 251161591149 is 941195161152.

251161591149 is a `hidden beast` number, since 2 + 5 + 1 + 16 + 1 + 591 + 1 + 49 = 666.

It is not a de Polignac number, because 251161591149 - 2⁴ = 251161591133 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251161591189) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1993345899 + ... + 1993346024.

It is an arithmetic number, because the mean of its divisors is an integer number (34551330008).

Almost surely, 2^251161591149 is an apocalyptic number.

It is an amenable number.

251161591149 is a deficient number, since it is larger than the sum of its proper divisors (163454368947).

251161591149 is a wasteful number, since it uses less digits than its factorization.

251161591149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3986691936 (or 3986691933 counting only the distinct ones).

The product of its digits is 97200, while the sum is 45.

The spelling of 251161591149 in words is "two hundred fifty-one billion, one hundred sixty-one million, five hundred ninety-one thousand, one hundred forty-nine".