251087878687 has 2 divisors, whose sum is σ = 251087878688. Its totient is φ = 251087878686.

The previous prime is 251087878673. The next prime is 251087878703. The reversal of 251087878687 is 786878780152.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 251087878687 - 2¹⁵ = 251087845919 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251087878627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125543939343 + 125543939344.

It is an arithmetic number, because the mean of its divisors is an integer number (125543939344).

Almost surely, 2^251087878687 is an apocalyptic number.

251087878687 is a deficient number, since it is larger than the sum of its proper divisors (1).

251087878687 is an equidigital number, since it uses as much as digits as its factorization.

251087878687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84295680, while the sum is 67.

The spelling of 251087878687 in words is "two hundred fifty-one billion, eighty-seven million, eight hundred seventy-eight thousand, six hundred eighty-seven".