78318121792 has 28 divisors (see below), whose sum is σ = 155942978436. Its totient is φ = 39025402880.

The previous prime is 78318121789. The next prime is 78318121873. The reversal of 78318121792 is 29712181387.

It can be written as a sum of positive squares in 2 ways, for example, as 66597028096 + 11721093696 = 258064^2 + 108264^2 .

It is a super-2 number, since 2×78318121792² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 2069509 + ... + 2107012.

It is an arithmetic number, because the mean of its divisors is an integer number (5569392087).

Almost surely, 2^78318121792 is an apocalyptic number.

It is an amenable number.

78318121792 is a deficient number, since it is larger than the sum of its proper divisors (77624856644).

78318121792 is a wasteful number, since it uses less digits than its factorization.

78318121792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4176826 (or 4176816 counting only the distinct ones).

The product of its digits is 338688, while the sum is 49.

The spelling of 78318121792 in words is "seventy-eight billion, three hundred eighteen million, one hundred twenty-one thousand, seven hundred ninety-two".