681939789 has 8 divisors (see below), whose sum is σ = 909778752. Its totient is φ = 454363680.

The previous prime is 681939781. The next prime is 681939821. The reversal of 681939789 is 987939186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 681939789 - 2³ = 681939781 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681939781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59577 + ... + 70094.

It is an arithmetic number, because the mean of its divisors is an integer number (113722344).

Almost surely, 2^681939789 is an apocalyptic number.

It is an amenable number.

681939789 is a deficient number, since it is larger than the sum of its proper divisors (227838963).

681939789 is a wasteful number, since it uses less digits than its factorization.

681939789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131427.

The product of its digits is 5878656, while the sum is 60.

The square root of 681939789 is about 26113.9768897807. The cubic root of 681939789 is about 880.2013094028.

The spelling of 681939789 in words is "six hundred eighty-one million, nine hundred thirty-nine thousand, seven hundred eighty-nine".