251742 has 8 divisors (see below), whose sum is σ = 503496. Its totient is φ = 83912.

The previous prime is 251737. The next prime is 251761. The reversal of 251742 is 247152.

251742 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

251742 is an admirable number.

It is an Ulam number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 251742.

It is an unprimeable number.

251742 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20973 + ... + 20984.

It is an arithmetic number, because the mean of its divisors is an integer number (62937).

2²⁵¹⁷⁴² is an apocalyptic number.

251742 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.

251742 is a wasteful number, since it uses less digits than its factorization.

251742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41962.

The product of its digits is 560, while the sum is 21.

The square root of 251742 is about 501.7389759626. The cubic root of 251742 is about 63.1420327856.

Adding to 251742 its reverse (247152), we get a palindrome (498894).

The spelling of 251742 in words is "two hundred fifty-one thousand, seven hundred forty-two".