78840142 has 4 divisors (see below), whose sum is σ = 118260216. Its totient is φ = 39420070.

The previous prime is 78840137. The next prime is 78840143. The reversal of 78840142 is 24104887.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 78840098 and 78840107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78840143) 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 as a sum of consecutive naturals, namely, 19710034 + ... + 19710037.

It is an arithmetic number, because the mean of its divisors is an integer number (29565054).

Almost surely, 2^78840142 is an apocalyptic number.

78840142 is a deficient number, since it is larger than the sum of its proper divisors (39420074).

78840142 is a wasteful number, since it uses less digits than its factorization.

78840142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39420073.

The product of its (nonzero) digits is 14336, while the sum is 34.

The square root of 78840142 is about 8879.1971483913. The cubic root of 78840142 is about 428.7944273648.

The spelling of 78840142 in words is "seventy-eight million, eight hundred forty thousand, one hundred forty-two".