78343223729 has 4 divisors (see below), whose sum is σ = 78374302500. Its totient is φ = 78312144960.

The previous prime is 78343223701. The next prime is 78343223731. The reversal of 78343223729 is 92732234387.

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 25240630129 + 53102593600 = 158873^2 + 230440^2 .

It is a cyclic number.

It is not a de Polignac number, because 78343223729 - 2²⁸ = 78074788273 is a prime.

It is a super-2 number, since 2×78343223729² (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 (78343223779) 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, 15535604 + ... + 15540645.

It is an arithmetic number, because the mean of its divisors is an integer number (19593575625).

Almost surely, 2^78343223729 is an apocalyptic number.

It is an amenable number.

78343223729 is a deficient number, since it is larger than the sum of its proper divisors (31078771).

78343223729 is a wasteful number, since it uses less digits than its factorization.

78343223729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31078770.

The product of its digits is 3048192, while the sum is 50.

The spelling of 78343223729 in words is "seventy-eight billion, three hundred forty-three million, two hundred twenty-three thousand, seven hundred twenty-nine".