42139858 has 4 divisors (see below), whose sum is σ = 63209790. Its totient is φ = 21069928.

The previous prime is 42139829. The next prime is 42139879. The reversal of 42139858 is 85893124.

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

It can be written as a sum of positive squares in only one way, i.e., 27217089 + 14922769 = 5217^2 + 3863^2 .

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 self number, because there is not a number n which added to its sum of digits gives 42139858.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10534963 + ... + 10534966.

Almost surely, 2^42139858 is an apocalyptic number.

42139858 is a deficient number, since it is larger than the sum of its proper divisors (21069932).

42139858 is a wasteful number, since it uses less digits than its factorization.

42139858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21069931.

The product of its digits is 69120, while the sum is 40.

The square root of 42139858 is about 6491.5220095136. The cubic root of 42139858 is about 347.9880704503.

The spelling of 42139858 in words is "forty-two million, one hundred thirty-nine thousand, eight hundred fifty-eight".