251261511051 has 8 divisors (see below), whose sum is σ = 335018647440. Its totient is φ = 167506024352.

The previous prime is 251261511049. The next prime is 251261511071. The reversal of 251261511051 is 150115162152.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 251261511051 - 2¹ = 251261511049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (251261511071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2641 + ... + 708893.

It is an arithmetic number, because the mean of its divisors is an integer number (41877330930).

Almost surely, 2^251261511051 is an apocalyptic number.

251261511051 is a deficient number, since it is larger than the sum of its proper divisors (83757136389).

251261511051 is a wasteful number, since it uses less digits than its factorization.

251261511051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 824845.

The product of its (nonzero) digits is 3000, while the sum is 30.

The spelling of 251261511051 in words is "two hundred fifty-one billion, two hundred sixty-one million, five hundred eleven thousand, fifty-one".