84000078 has 40 divisors (see below), whose sum is σ = 190827648. Its totient is φ = 27612576.

The previous prime is 84000073. The next prime is 84000079. The reversal of 84000078 is 87000048.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84000073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8275 + ... + 15377.

Almost surely, 2^84000078 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84000078, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95413824).

84000078 is an abundant number, since it is smaller than the sum of its proper divisors (106827570).

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

84000078 is a wasteful number, since it uses less digits than its factorization.

84000078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7190 (or 7181 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 84000078 is about 9165.1556451596. The cubic root of 84000078 is about 437.9520495453.

The spelling of 84000078 in words is "eighty-four million, seventy-eight", and thus it is an aban number.