681965833 has 8 divisors (see below), whose sum is σ = 717481800. Its totient is φ = 647349120.

The previous prime is 681965819. The next prime is 681965839. The reversal of 681965833 is 338569186.

It can be written as a sum of positive squares in 4 ways, for example, as 125619264 + 556346569 = 11208^2 + 23587^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681965833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (681965839) 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, 223258 + ... + 226291.

It is an arithmetic number, because the mean of its divisors is an integer number (89685225).

Almost surely, 2^681965833 is an apocalyptic number.

It is an amenable number.

681965833 is a deficient number, since it is larger than the sum of its proper divisors (35515967).

681965833 is a wasteful number, since it uses less digits than its factorization.

681965833 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449627.

The product of its digits is 933120, while the sum is 49.

The square root of 681965833 is about 26114.4755451837. The cubic root of 681965833 is about 880.2125145324.

The spelling of 681965833 in words is "six hundred eighty-one million, nine hundred sixty-five thousand, eight hundred thirty-three".