681843261 has 8 divisors (see below), whose sum is σ = 991772064. Its totient is φ = 413238320.

The previous prime is 681843247. The next prime is 681843277. The reversal of 681843261 is 162348186.

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

It is not a de Polignac number, because 681843261 - 2⁵ = 681843229 is a prime.

It is a super-2 number, since 2×681843261² = 929820465142228242, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681843661) by changing a digit.

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, 10330926 + ... + 10330991.

It is an arithmetic number, because the mean of its divisors is an integer number (123971508).

Almost surely, 2^681843261 is an apocalyptic number.

It is an amenable number.

681843261 is a deficient number, since it is larger than the sum of its proper divisors (309928803).

681843261 is a wasteful number, since it uses less digits than its factorization.

681843261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20661931.

The product of its digits is 55296, while the sum is 39.

The square root of 681843261 is about 26112.1286187090. The cubic root of 681843261 is about 880.1597768596.

The spelling of 681843261 in words is "six hundred eighty-one million, eight hundred forty-three thousand, two hundred sixty-one".