840788681 has 8 divisors (see below), whose sum is σ = 875417928. Its totient is φ = 806832000.

The previous prime is 840788671. The next prime is 840788699. The reversal of 840788681 is 186887048.

840788681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 149940025 + 690848656 = 12245^2 + 26284^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 840788681 - 2¹⁰ = 840787657 is a prime.

It is a super-2 number, since 2×840788681² = 1413851212195439522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (840788651) 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, 165590 + ... + 170591.

It is an arithmetic number, because the mean of its divisors is an integer number (109427241).

Almost surely, 2^840788681 is an apocalyptic number.

It is an amenable number.

840788681 is a deficient number, since it is larger than the sum of its proper divisors (34629247).

840788681 is a wasteful number, since it uses less digits than its factorization.

840788681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336283.

The product of its (nonzero) digits is 688128, while the sum is 50.

The square root of 840788681 is about 28996.3563400645. The cubic root of 840788681 is about 943.8340017564.

The spelling of 840788681 in words is "eight hundred forty million, seven hundred eighty-eight thousand, six hundred eighty-one".