42678391 has 4 divisors (see below), whose sum is σ = 48775312. Its totient is φ = 36581472.

The previous prime is 42678373. The next prime is 42678431. The reversal of 42678391 is 19387624.

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 42678391 - 2¹⁵ = 42645623 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 (42678301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3048450 + ... + 3048463.

It is an arithmetic number, because the mean of its divisors is an integer number (12193828).

Almost surely, 2^42678391 is an apocalyptic number.

42678391 is a deficient number, since it is larger than the sum of its proper divisors (6096921).

42678391 is an equidigital number, since it uses as much as digits as its factorization.

42678391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6096920.

The product of its digits is 72576, while the sum is 40.

The square root of 42678391 is about 6532.8700430974. The cubic root of 42678391 is about 349.4641896775.

The spelling of 42678391 in words is "forty-two million, six hundred seventy-eight thousand, three hundred ninety-one".