78833917681 has 4 divisors (see below), whose sum is σ = 78834926500. Its totient is φ = 78832908864.

The previous prime is 78833917667. The next prime is 78833917691. The reversal of 78833917681 is 18671933887.

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 38368974400 + 40464943281 = 195880^2 + 201159^2 .

It is a cyclic number.

It is not a de Polignac number, because 78833917681 - 2⁵ = 78833917649 is a prime.

It is a super-2 number, since 2×78833917681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78833917601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376356 + ... + 547093.

It is an arithmetic number, because the mean of its divisors is an integer number (19708731625).

Almost surely, 2^78833917681 is an apocalyptic number.

It is an amenable number.

78833917681 is a deficient number, since it is larger than the sum of its proper divisors (1008819).

78833917681 is an equidigital number, since it uses as much as digits as its factorization.

78833917681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1008818.

The product of its digits is 12192768, while the sum is 61.

The spelling of 78833917681 in words is "seventy-eight billion, eight hundred thirty-three million, nine hundred seventeen thousand, six hundred eighty-one".