251087878729 has 2 divisors, whose sum is σ = 251087878730. Its totient is φ = 251087878728.

The previous prime is 251087878703. The next prime is 251087878733. The reversal of 251087878729 is 927878780152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 232756072704 + 18331806025 = 482448^2 + 135395^2 .

It is a cyclic number.

It is not a de Polignac number, because 251087878729 - 2²⁷ = 250953661001 is a prime.

It is not a weakly prime, because it can be changed into another prime (251087878799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125543939364 + 125543939365.

It is an arithmetic number, because the mean of its divisors is an integer number (125543939365).

Almost surely, 2^251087878729 is an apocalyptic number.

It is an amenable number.

251087878729 is a deficient number, since it is larger than the sum of its proper divisors (1).

251087878729 is an equidigital number, since it uses as much as digits as its factorization.

251087878729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31610880, while the sum is 64.

The spelling of 251087878729 in words is "two hundred fifty-one billion, eighty-seven million, eight hundred seventy-eight thousand, seven hundred twenty-nine".