78394603685 has 16 divisors (see below), whose sum is σ = 94191059952. Its totient is φ = 62637388800.

The previous prime is 78394603681. The next prime is 78394603691. The reversal of 78394603685 is 58630649387.

It can be written as a sum of positive squares in 8 ways, for example, as 250873921 + 78143729764 = 15839^2 + 279542^2 .

It is not a de Polignac number, because 78394603685 - 2² = 78394603681 is a prime.

It is a super-3 number, since 3×78394603685³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78394603681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20842205 + ... + 20845965.

It is an arithmetic number, because the mean of its divisors is an integer number (5886941247).

Almost surely, 2^78394603685 is an apocalyptic number.

It is an amenable number.

78394603685 is a deficient number, since it is larger than the sum of its proper divisors (15796456267).

78394603685 is a wasteful number, since it uses less digits than its factorization.

78394603685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7864.

The product of its (nonzero) digits is 26127360, while the sum is 59.

The spelling of 78394603685 in words is "seventy-eight billion, three hundred ninety-four million, six hundred three thousand, six hundred eighty-five".