251322749 has 2 divisors, whose sum is σ = 251322750. Its totient is φ = 251322748.

The previous prime is 251322727. The next prime is 251322821. The reversal of 251322749 is 947223152.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 242020249 + 9302500 = 15557^2 + 3050^2 .

It is a cyclic number.

It is not a de Polignac number, because 251322749 - 2⁸ = 251322493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251322719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125661374 + 125661375.

It is an arithmetic number, because the mean of its divisors is an integer number (125661375).

Almost surely, 2^251322749 is an apocalyptic number.

It is an amenable number.

251322749 is a deficient number, since it is larger than the sum of its proper divisors (1).

251322749 is an equidigital number, since it uses as much as digits as its factorization.

251322749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 35.

The square root of 251322749 is about 15853.1621135974. The cubic root of 251322749 is about 631.0696107243.

The spelling of 251322749 in words is "two hundred fifty-one million, three hundred twenty-two thousand, seven hundred forty-nine".