78298320989 has 4 divisors (see below), whose sum is σ = 89483795424. Its totient is φ = 67112846556.

The previous prime is 78298320949. The next prime is 78298321007. The reversal of 78298320989 is 98902389287.

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 de Polignac number, because none of the positive numbers 2^k-78298320989 is a prime.

It is a super-2 number, since 2×78298320989² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78298320949) 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, 5592737207 + ... + 5592737220.

It is an arithmetic number, because the mean of its divisors is an integer number (22370948856).

Almost surely, 2^78298320989 is an apocalyptic number.

It is an amenable number.

78298320989 is a deficient number, since it is larger than the sum of its proper divisors (11185474435).

78298320989 is a wasteful number, since it uses less digits than its factorization.

78298320989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11185474434.

The product of its (nonzero) digits is 31352832, while the sum is 65.

The spelling of 78298320989 in words is "seventy-eight billion, two hundred ninety-eight million, three hundred twenty thousand, nine hundred eighty-nine".