251520242 has 8 divisors (see below), whose sum is σ = 377525232. Its totient is φ = 125678500.

The previous prime is 251520209. The next prime is 251520251. The reversal of 251520242 is 242025152.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 36884 + ... + 43167.

It is an arithmetic number, because the mean of its divisors is an integer number (47190654).

Almost surely, 2^251520242 is an apocalyptic number.

251520242 is a deficient number, since it is larger than the sum of its proper divisors (126004990).

251520242 is a wasteful number, since it uses less digits than its factorization.

251520242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81624.

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 251520242 is about 15859.3897108306. The cubic root of 251520242 is about 631.2348686109.

Adding to 251520242 its reverse (242025152), we get a palindrome (493545394).

The spelling of 251520242 in words is "two hundred fifty-one million, five hundred twenty thousand, two hundred forty-two".