251261535412 has 12 divisors (see below), whose sum is σ = 450432264996. Its totient is φ = 122566602560.

The previous prime is 251261535407. The next prime is 251261535431. The reversal of 251261535412 is 214535162152.

It can be written as a sum of positive squares in 2 ways, for example, as 8435320336 + 242826215076 = 91844^2 + 492774^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 766041103 + ... + 766041430.

It is an arithmetic number, because the mean of its divisors is an integer number (37536022083).

Almost surely, 2^251261535412 is an apocalyptic number.

It is an amenable number.

251261535412 is a deficient number, since it is larger than the sum of its proper divisors (199170729584).

251261535412 is a wasteful number, since it uses less digits than its factorization.

251261535412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1532082578 (or 1532082576 counting only the distinct ones).

The product of its digits is 72000, while the sum is 37.

Adding to 251261535412 its reverse (214535162152), we get a palindrome (465796697564).

The spelling of 251261535412 in words is "two hundred fifty-one billion, two hundred sixty-one million, five hundred thirty-five thousand, four hundred twelve".