1251728684 has 12 divisors (see below), whose sum is σ = 2191047264. Its totient is φ = 625715184.

The previous prime is 1251728677. The next prime is 1251728689. The reversal of 1251728684 is 4868271521.

It is not an unprimeable number, because it can be changed into a prime (1251728689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17207 + ... + 52910.

It is an arithmetic number, because the mean of its divisors is an integer number (182587272).

Almost surely, 2^1251728684 is an apocalyptic number.

It is an amenable number.

1251728684 is a deficient number, since it is larger than the sum of its proper divisors (939318580).

1251728684 is a wasteful number, since it uses less digits than its factorization.

1251728684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74584 (or 74582 counting only the distinct ones).

The product of its digits is 215040, while the sum is 44.

The square root of 1251728684 is about 35379.7778964199. Note that the first 3 decimals coincide. The cubic root of 1251728684 is about 1077.7136945149.

The spelling of 1251728684 in words is "one billion, two hundred fifty-one million, seven hundred twenty-eight thousand, six hundred eighty-four".