78289999 has 8 divisors (see below), whose sum is σ = 82680192. Its totient is φ = 73982040.

The previous prime is 78289997. The next prime is 78290021. The reversal of 78289999 is 99998287.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78289999 - 2¹ = 78289997 is a prime.

It is a super-2 number, since 2×78289999² = 12258647886840002, which contains 22 as substring.

It is a Duffinian number.

78289999 is a modest number, since divided by 9999 gives 7828 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78289997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18597 + ... + 22414.

It is an arithmetic number, because the mean of its divisors is an integer number (10335024).

Almost surely, 2^78289999 is an apocalyptic number.

78289999 is a deficient number, since it is larger than the sum of its proper divisors (4390193).

78289999 is a wasteful number, since it uses less digits than its factorization.

78289999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41117.

The product of its digits is 5878656, while the sum is 61.

The square root of 78289999 is about 8848.1635947806. The cubic root of 78289999 is about 427.7947289898.

The spelling of 78289999 in words is "seventy-eight million, two hundred eighty-nine thousand, nine hundred ninety-nine".