678142 has 4 divisors (see below), whose sum is σ = 1017216. Its totient is φ = 339070.

The previous prime is 678133. The next prime is 678157. The reversal of 678142 is 241876.

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

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 678142.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 169534 + ... + 169537.

It is an arithmetic number, because the mean of its divisors is an integer number (254304).

2⁶⁷⁸¹⁴² is an apocalyptic number.

678142 is a deficient number, since it is larger than the sum of its proper divisors (339074).

678142 is a wasteful number, since it uses less digits than its factorization.

678142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339073.

The product of its digits is 2688, while the sum is 28.

The square root of 678142 is about 823.4937765399. The cubic root of 678142 is about 87.8564291164.

It can be divided in two parts, 678 and 142, that added together give a triangular number (820 = T₄₀).

The spelling of 678142 in words is "six hundred seventy-eight thousand, one hundred forty-two".