78740339729 has 4 divisors (see below), whose sum is σ = 81280350720. Its totient is φ = 76200328740.

The previous prime is 78740339707. The next prime is 78740339737. The reversal of 78740339729 is 92793304787.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78740339729 is a prime.

It is a super-2 number, since 2×78740339729² (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 (78740339779) 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, 1270005449 + ... + 1270005510.

It is an arithmetic number, because the mean of its divisors is an integer number (20320087680).

Almost surely, 2^78740339729 is an apocalyptic number.

It is an amenable number.

78740339729 is a deficient number, since it is larger than the sum of its proper divisors (2540010991).

78740339729 is a wasteful number, since it uses less digits than its factorization.

78740339729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2540010990.

The product of its (nonzero) digits is 16003008, while the sum is 59.

The spelling of 78740339729 in words is "seventy-eight billion, seven hundred forty million, three hundred thirty-nine thousand, seven hundred twenty-nine".