681621692 has 24 divisors (see below), whose sum is σ = 1199839872. Its totient is φ = 338817600.

The previous prime is 681621673. The next prime is 681621709. The reversal of 681621692 is 296126186.

It is a happy number.

It is a congruent number.

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, 687317 + ... + 688307.

It is an arithmetic number, because the mean of its divisors is an integer number (49993328).

Almost surely, 2^681621692 is an apocalyptic number.

It is an amenable number.

681621692 is a deficient number, since it is larger than the sum of its proper divisors (518218180).

681621692 is a wasteful number, since it uses less digits than its factorization.

681621692 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1829 (or 1827 counting only the distinct ones).

The product of its digits is 62208, while the sum is 41.

The square root of 681621692 is about 26107.8856286755. The cubic root of 681621692 is about 880.0644288227.

The spelling of 681621692 in words is "six hundred eighty-one million, six hundred twenty-one thousand, six hundred ninety-two".