251023243 has 4 divisors (see below), whose sum is σ = 251977968. Its totient is φ = 250068520.

The previous prime is 251023189. The next prime is 251023261. The reversal of 251023243 is 342320152.

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

It is a cyclic number.

It is not a de Polignac number, because 251023243 - 2²¹ = 248926091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251023943) 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, 476968 + ... + 477493.

It is an arithmetic number, because the mean of its divisors is an integer number (62994492).

Almost surely, 2^251023243 is an apocalyptic number.

251023243 is a deficient number, since it is larger than the sum of its proper divisors (954725).

251023243 is an equidigital number, since it uses as much as digits as its factorization.

251023243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 954724.

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 251023243 is about 15843.7130433494. The cubic root of 251023243 is about 630.8188252738.

Adding to 251023243 its reverse (342320152), we get a palindrome (593343395).

The spelling of 251023243 in words is "two hundred fifty-one million, twenty-three thousand, two hundred forty-three".