681989735 has 16 divisors (see below), whose sum is σ = 960580416. Its totient is φ = 455010048.

The previous prime is 681989729. The next prime is 681989741. The reversal of 681989735 is 537989186.

681989735 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (681989729) and next prime (681989741).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681989735 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 262022 + ... + 264611.

It is an arithmetic number, because the mean of its divisors is an integer number (60036276).

Almost surely, 2^681989735 is an apocalyptic number.

681989735 is a deficient number, since it is larger than the sum of its proper divisors (278590681).

681989735 is a wasteful number, since it uses less digits than its factorization.

681989735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526682.

The product of its digits is 3265920, while the sum is 56.

The square root of 681989735 is about 26114.9331800792. The cubic root of 681989735 is about 880.2227978402. Note that the first 3 decimals are identical.

The spelling of 681989735 in words is "six hundred eighty-one million, nine hundred eighty-nine thousand, seven hundred thirty-five".