78424140 has 24 divisors (see below), whose sum is σ = 219587760. Its totient is φ = 20913088.

The previous prime is 78424121. The next prime is 78424163. The reversal of 78424140 is 4142487.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 78424098 and 78424107.

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 7 ways as a sum of consecutive naturals, for example, 653475 + ... + 653594.

It is an arithmetic number, because the mean of its divisors is an integer number (9149490).

Almost surely, 2^78424140 is an apocalyptic number.

It is an amenable number.

78424140 is an abundant number, since it is smaller than the sum of its proper divisors (141163620).

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

78424140 is a wasteful number, since it uses less digits than its factorization.

78424140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1307081 (or 1307079 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 30.

The square root of 78424140 is about 8855.7405111035. The cubic root of 78424140 is about 428.0389154355.

The spelling of 78424140 in words is "seventy-eight million, four hundred twenty-four thousand, one hundred forty".