251268289 has 2 divisors, whose sum is σ = 251268290. Its totient is φ = 251268288.

The previous prime is 251268247. The next prime is 251268317. The reversal of 251268289 is 982862152.

251268289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 193766400 + 57501889 = 13920^2 + 7583^2 .

It is a cyclic number.

It is not a de Polignac number, because 251268289 - 2⁷ = 251268161 is a prime.

It is not a weakly prime, because it can be changed into another prime (251268229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125634144 + 125634145.

It is an arithmetic number, because the mean of its divisors is an integer number (125634145).

Almost surely, 2^251268289 is an apocalyptic number.

It is an amenable number.

251268289 is a deficient number, since it is larger than the sum of its proper divisors (1).

251268289 is an equidigital number, since it uses as much as digits as its factorization.

251268289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 43.

The square root of 251268289 is about 15851.4443821375. Note that the first 3 decimals coincide. The cubic root of 251268289 is about 631.0240245423.

The spelling of 251268289 in words is "two hundred fifty-one million, two hundred sixty-eight thousand, two hundred eighty-nine".