42878239 has 4 divisors (see below), whose sum is σ = 44261440. Its totient is φ = 41495040.

The previous prime is 42878201. The next prime is 42878261. The reversal of 42878239 is 93287824.

It is a happy number.

42878239 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 42878239 - 2¹⁵ = 42845471 is a prime.

It is a super-2 number, since 2×42878239² = 3677086759482242, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42878195 and 42878204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42878299) 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 3 ways as a sum of consecutive naturals, for example, 691554 + ... + 691615.

It is an arithmetic number, because the mean of its divisors is an integer number (11065360).

Almost surely, 2^42878239 is an apocalyptic number.

42878239 is a deficient number, since it is larger than the sum of its proper divisors (1383201).

42878239 is a wasteful number, since it uses less digits than its factorization.

42878239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1383200.

The product of its digits is 193536, while the sum is 43.

The square root of 42878239 is about 6548.1477533727. The cubic root of 42878239 is about 350.0088133835.

The spelling of 42878239 in words is "forty-two million, eight hundred seventy-eight thousand, two hundred thirty-nine".