681217256 has 32 divisors (see below), whose sum is σ = 1305887400. Its totient is φ = 333047040.

The previous prime is 681217169. The next prime is 681217297. The reversal of 681217256 is 652712186.

It can be written as a sum of positive squares in 4 ways, for example, as 314494756 + 366722500 = 17734^2 + 19150^2 .

It is an unprimeable 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 7 ways as a sum of consecutive naturals, for example, 80390 + ... + 88458.

Almost surely, 2^681217256 is an apocalyptic number.

It is an amenable number.

681217256 is a deficient number, since it is larger than the sum of its proper divisors (624670144).

681217256 is a wasteful number, since it uses less digits than its factorization.

681217256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8309 (or 8305 counting only the distinct ones).

The product of its digits is 40320, while the sum is 38.

The square root of 681217256 is about 26100.1390034613. The cubic root of 681217256 is about 879.8903341301.

The spelling of 681217256 in words is "six hundred eighty-one million, two hundred seventeen thousand, two hundred fifty-six".