251728668 has 48 divisors (see below), whose sum is σ = 659988000. Its totient is φ = 82963584.

The previous prime is 251728661. The next prime is 251728693. The reversal of 251728668 is 866827152.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251728661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3483 + ... + 22706.

It is an arithmetic number, because the mean of its divisors is an integer number (13749750).

Almost surely, 2^251728668 is an apocalyptic number.

It is an amenable number.

251728668 is an abundant number, since it is smaller than the sum of its proper divisors (408259332).

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

251728668 is a wasteful number, since it uses less digits than its factorization.

251728668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26291 (or 26283 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 251728668 is about 15865.9594100073. The cubic root of 251728668 is about 631.4091812005.

The spelling of 251728668 in words is "two hundred fifty-one million, seven hundred twenty-eight thousand, six hundred sixty-eight".