681188851933 has 4 divisors (see below), whose sum is σ = 681279238780. Its totient is φ = 681098465088.

The previous prime is 681188851913. The next prime is 681188851943. The reversal of 681188851933 is 339158881186.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 504706522329 + 176482329604 = 710427^2 + 420098^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681188851933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681188851913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45182118 + ... + 45197191.

It is an arithmetic number, because the mean of its divisors is an integer number (170319809695).

Almost surely, 2^681188851933 is an apocalyptic number.

It is an amenable number.

681188851933 is a deficient number, since it is larger than the sum of its proper divisors (90386847).

681188851933 is an equidigital number, since it uses as much as digits as its factorization.

681188851933 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90386846.

The product of its digits is 9953280, while the sum is 61.

The spelling of 681188851933 in words is "six hundred eighty-one billion, one hundred eighty-eight million, eight hundred fifty-one thousand, nine hundred thirty-three".