251766 has 24 divisors (see below), whose sum is σ = 555984. Its totient is φ = 82320.

The previous prime is 251761. The next prime is 251789. The reversal of 251766 is 667152.

It is a super-2 number, since 2×251766² = 126772237512, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251761) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 1180 + ... + 1376.

It is an arithmetic number, because the mean of its divisors is an integer number (23166).

2²⁵¹⁷⁶⁶ is an apocalyptic number.

251766 is an abundant number, since it is smaller than the sum of its proper divisors (304218).

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

251766 is a wasteful number, since it uses less digits than its factorization.

251766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276 (or 273 counting only the distinct ones).

The product of its digits is 2520, while the sum is 27.

The square root of 251766 is about 501.7628922111. The cubic root of 251766 is about 63.1440392852.

The spelling of 251766 in words is "two hundred fifty-one thousand, seven hundred sixty-six".