251530291 has 2 divisors, whose sum is σ = 251530292. Its totient is φ = 251530290.

The previous prime is 251530273. The next prime is 251530297. The reversal of 251530291 is 192035152.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 251530291 - 2⁵ = 251530259 is a prime.

It is not a weakly prime, because it can be changed into another prime (251530297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125765145 + 125765146.

It is an arithmetic number, because the mean of its divisors is an integer number (125765146).

Almost surely, 2^251530291 is an apocalyptic number.

251530291 is a deficient number, since it is larger than the sum of its proper divisors (1).

251530291 is an equidigital number, since it uses as much as digits as its factorization.

251530291 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 251530291 is about 15859.7065231359. The cubic root of 251530291 is about 631.2432750844.

The spelling of 251530291 in words is "two hundred fifty-one million, five hundred thirty thousand, two hundred ninety-one".