84378778 has 8 divisors (see below), whose sum is σ = 138074400. Its totient is φ = 38353980.

The previous prime is 84378757. The next prime is 84378787. The reversal of 84378778 is 87787348.

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

It is an unprimeable number.

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, 1917678 + ... + 1917721.

It is an arithmetic number, because the mean of its divisors is an integer number (17259300).

Almost surely, 2^84378778 is an apocalyptic number.

84378778 is a deficient number, since it is larger than the sum of its proper divisors (53695622).

84378778 is a wasteful number, since it uses less digits than its factorization.

84378778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3835412.

The product of its digits is 2107392, while the sum is 52.

The square root of 84378778 is about 9185.7921814071. The cubic root of 84378778 is about 438.6092069685.

The spelling of 84378778 in words is "eighty-four million, three hundred seventy-eight thousand, seven hundred seventy-eight".