42278389 has 8 divisors (see below), whose sum is σ = 43831040. Its totient is φ = 40737600.

The previous prime is 42278359. The next prime is 42278399. The reversal of 42278389 is 98387224.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 42278389 - 2⁷ = 42278261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42278329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4642 + ... + 10300.

It is an arithmetic number, because the mean of its divisors is an integer number (5478880).

Almost surely, 2^42278389 is an apocalyptic number.

It is an amenable number.

42278389 is a deficient number, since it is larger than the sum of its proper divisors (1552651).

42278389 is a wasteful number, since it uses less digits than its factorization.

42278389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5931.

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

The square root of 42278389 is about 6502.1834025195. The cubic root of 42278389 is about 348.3689798663.

The spelling of 42278389 in words is "forty-two million, two hundred seventy-eight thousand, three hundred eighty-nine".