251764987 has 2 divisors, whose sum is σ = 251764988. Its totient is φ = 251764986.

The previous prime is 251764973. The next prime is 251765071. The reversal of 251764987 is 789467152.

251764987 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 251764987 - 2¹⁹ = 251240699 is a prime.

It is a super-2 number, since 2×251764987² = 126771217358220338, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 251764987.

It is not a weakly prime, because it can be changed into another prime (251764907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125882493 + 125882494.

It is an arithmetic number, because the mean of its divisors is an integer number (125882494).

Almost surely, 2^251764987 is an apocalyptic number.

251764987 is a deficient number, since it is larger than the sum of its proper divisors (1).

251764987 is an equidigital number, since it uses as much as digits as its factorization.

251764987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 846720, while the sum is 49.

The square root of 251764987 is about 15867.1039260478. The cubic root of 251764987 is about 631.4395459678.

The spelling of 251764987 in words is "two hundred fifty-one million, seven hundred sixty-four thousand, nine hundred eighty-seven".