251248791 has 4 divisors (see below), whose sum is σ = 334998392. Its totient is φ = 167499192.

The previous prime is 251248787. The next prime is 251248801. The reversal of 251248791 is 197842152.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 251248791 - 2² = 251248787 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251248891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41874796 + ... + 41874801.

It is an arithmetic number, because the mean of its divisors is an integer number (83749598).

Almost surely, 2^251248791 is an apocalyptic number.

251248791 is a deficient number, since it is larger than the sum of its proper divisors (83749601).

251248791 is an equidigital number, since it uses as much as digits as its factorization.

251248791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83749600.

The product of its digits is 40320, while the sum is 39.

The square root of 251248791 is about 15850.8293473875. The cubic root of 251248791 is about 631.0077019830.

The spelling of 251248791 in words is "two hundred fifty-one million, two hundred forty-eight thousand, seven hundred ninety-one".