251005242 has 8 divisors (see below), whose sum is σ = 502010496. Its totient is φ = 83668412.

The previous prime is 251005231. The next prime is 251005253. The reversal of 251005242 is 242500152.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (251005231) and next prime (251005253).

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

251005242 is an admirable number.

It is a super-2 number, since 2×251005242² = 126007263022957128, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20917098 + ... + 20917109.

It is an arithmetic number, because the mean of its divisors is an integer number (62751312).

Almost surely, 2^251005242 is an apocalyptic number.

251005242 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

251005242 is a wasteful number, since it uses less digits than its factorization.

251005242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41834212.

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 251005242 is about 15843.1449529442. The cubic root of 251005242 is about 630.8037461375.

Adding to 251005242 its reverse (242500152), we get a palindrome (493505394).

The spelling of 251005242 in words is "two hundred fifty-one million, five thousand, two hundred forty-two".