78669317881 has 16 divisors (see below), whose sum is σ = 99262937088. Its totient is φ = 60562198800.

The previous prime is 78669317873. The next prime is 78669317887. The reversal of 78669317881 is 18871396687.

It is a cyclic number.

It is not a de Polignac number, because 78669317881 - 2³ = 78669317873 is a prime.

It is a super-2 number, since 2×78669317881² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78669317887) 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 15 ways as a sum of consecutive naturals, for example, 6148305 + ... + 6161086.

It is an arithmetic number, because the mean of its divisors is an integer number (6203933568).

Almost surely, 2^78669317881 is an apocalyptic number.

It is an amenable number.

78669317881 is a deficient number, since it is larger than the sum of its proper divisors (20593619207).

78669317881 is a wasteful number, since it uses less digits than its factorization.

78669317881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12309492.

The product of its digits is 24385536, while the sum is 64.

The spelling of 78669317881 in words is "seventy-eight billion, six hundred sixty-nine million, three hundred seventeen thousand, eight hundred eighty-one".