42878137 has 4 divisors (see below), whose sum is σ = 43045236. Its totient is φ = 42711040.

The previous prime is 42878089. The next prime is 42878149. The reversal of 42878137 is 73187824.

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

It can be written as a sum of positive squares in 2 ways, for example, as 38638656 + 4239481 = 6216^2 + 2059^2 .

It is a cyclic number.

It is not a de Polignac number, because 42878137 - 2²³ = 34489529 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42878137.

It is not an unprimeable number, because it can be changed into a prime (42878167) 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, 83164 + ... + 83677.

It is an arithmetic number, because the mean of its divisors is an integer number (10761309).

Almost surely, 2^42878137 is an apocalyptic number.

It is an amenable number.

42878137 is a deficient number, since it is larger than the sum of its proper divisors (167099).

42878137 is a wasteful number, since it uses less digits than its factorization.

42878137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167098.

The product of its digits is 75264, while the sum is 40.

The square root of 42878137 is about 6548.1399649061. The cubic root of 42878137 is about 350.0085358462.

The spelling of 42878137 in words is "forty-two million, eight hundred seventy-eight thousand, one hundred thirty-seven".