681515706 has 32 divisors (see below), whose sum is σ = 1372871808. Its totient is φ = 225538560.

The previous prime is 681515701. The next prime is 681515707. The reversal of 681515706 is 607515186.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (681515701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 726870 + ... + 727806.

It is an arithmetic number, because the mean of its divisors is an integer number (42902244).

Almost surely, 2^681515706 is an apocalyptic number.

681515706 is an abundant number, since it is smaller than the sum of its proper divisors (691356102).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

681515706 is a wasteful number, since it uses less digits than its factorization.

681515706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1686.

The product of its (nonzero) digits is 50400, while the sum is 39.

The square root of 681515706 is about 26105.8557798820. The cubic root of 681515706 is about 880.0188124422.

The spelling of 681515706 in words is "six hundred eighty-one million, five hundred fifteen thousand, seven hundred six".