78889289 has 4 divisors (see below), whose sum is σ = 80813460. Its totient is φ = 76965120.

The previous prime is 78889277. The next prime is 78889301. The reversal of 78889289 is 98298887.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (78889277) and next prime (78889301).

It can be written as a sum of positive squares in 2 ways, for example, as 32581264 + 46308025 = 5708^2 + 6805^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78889289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78889189) 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, 962024 + ... + 962105.

It is an arithmetic number, because the mean of its divisors is an integer number (20203365).

Almost surely, 2^78889289 is an apocalyptic number.

It is an amenable number.

78889289 is a deficient number, since it is larger than the sum of its proper divisors (1924171).

78889289 is a wasteful number, since it uses less digits than its factorization.

78889289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1924170.

The product of its digits is 4644864, while the sum is 59.

The square root of 78889289 is about 8881.9642534746. The cubic root of 78889289 is about 428.8835088137.

The spelling of 78889289 in words is "seventy-eight million, eight hundred eighty-nine thousand, two hundred eighty-nine".