251495749 has 2 divisors, whose sum is σ = 251495750. Its totient is φ = 251495748.

The previous prime is 251495719. The next prime is 251495833. The reversal of 251495749 is 947594152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 139665124 + 111830625 = 11818^2 + 10575^2 .

It is a cyclic number.

It is not a de Polignac number, because 251495749 - 2¹¹ = 251493701 is a prime.

It is a super-2 number, since 2×251495749² = 126500223530142002, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 251495699 and 251495708.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251495719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125747874 + 125747875.

It is an arithmetic number, because the mean of its divisors is an integer number (125747875).

Almost surely, 2^251495749 is an apocalyptic number.

It is an amenable number.

251495749 is a deficient number, since it is larger than the sum of its proper divisors (1).

251495749 is an equidigital number, since it uses as much as digits as its factorization.

251495749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 46.

The square root of 251495749 is about 15858.6174996435. The cubic root of 251495749 is about 631.2143780964.

The spelling of 251495749 in words is "two hundred fifty-one million, four hundred ninety-five thousand, seven hundred forty-nine".