78205456289 has 4 divisors (see below), whose sum is σ = 78213716160. Its totient is φ = 78197196420.

The previous prime is 78205456253. The next prime is 78205456309. The reversal of 78205456289 is 98265450287.

It is a happy number.

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 not a de Polignac number, because 78205456289 - 2²⁰ = 78204407713 is a prime.

It is a super-2 number, since 2×78205456289² (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 (78205456489) 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 3 ways as a sum of consecutive naturals, for example, 4115717 + ... + 4134674.

It is an arithmetic number, because the mean of its divisors is an integer number (19553429040).

Almost surely, 2^78205456289 is an apocalyptic number.

It is an amenable number.

78205456289 is a deficient number, since it is larger than the sum of its proper divisors (8259871).

78205456289 is an equidigital number, since it uses as much as digits as its factorization.

78205456289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8259870.

The product of its (nonzero) digits is 9676800, while the sum is 56.

The spelling of 78205456289 in words is "seventy-eight billion, two hundred five million, four hundred fifty-six thousand, two hundred eighty-nine".