78499984 has 20 divisors (see below), whose sum is σ = 157339260. Its totient is φ = 37896320.

The previous prime is 78499979. The next prime is 78499987. The reversal of 78499984 is 48999487.

It can be written as a sum of positive squares in 2 ways, for example, as 24800400 + 53699584 = 4980^2 + 7328^2 .

It is a Harshad number since it is a multiple of its sum of digits (58).

It is not an unprimeable number, because it can be changed into a prime (78499987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 84127 + ... + 85054.

It is an arithmetic number, because the mean of its divisors is an integer number (7866963).

Almost surely, 2^78499984 is an apocalyptic number.

It is an amenable number.

78499984 is an abundant number, since it is smaller than the sum of its proper divisors (78839276).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78499984 is a wasteful number, since it uses less digits than its factorization.

78499984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169218 (or 169212 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 58.

The square root of 78499984 is about 8860.0216704024. The cubic root of 78499984 is about 428.1768564817.

The spelling of 78499984 in words is "seventy-eight million, four hundred ninety-nine thousand, nine hundred eighty-four".