251261147 has 2 divisors, whose sum is σ = 251261148. Its totient is φ = 251261146.

The previous prime is 251261141. The next prime is 251261237. The reversal of 251261147 is 741162152.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 251261147 - 2¹⁸ = 250999003 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (251261141) 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, 125630573 + 125630574.

It is an arithmetic number, because the mean of its divisors is an integer number (125630574).

Almost surely, 2^251261147 is an apocalyptic number.

251261147 is a deficient number, since it is larger than the sum of its proper divisors (1).

251261147 is an equidigital number, since it uses as much as digits as its factorization.

251261147 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 29.

The square root of 251261147 is about 15851.2191013814. The cubic root of 251261147 is about 631.0180457851.

The spelling of 251261147 in words is "two hundred fifty-one million, two hundred sixty-one thousand, one hundred forty-seven".