139042642 has 4 divisors (see below), whose sum is σ = 208563966. Its totient is φ = 69521320.

The previous prime is 139042639. The next prime is 139042661. The reversal of 139042642 is 246240931.

It is a happy number.

139042642 is digitally balanced in base 3, 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 can be written as a sum of positive squares in only one way, i.e., 131308681 + 7733961 = 11459^2 + 2781^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 34760659 + ... + 34760662.

Almost surely, 2^139042642 is an apocalyptic number.

139042642 is a deficient number, since it is larger than the sum of its proper divisors (69521324).

139042642 is an equidigital number, since it uses as much as digits as its factorization.

139042642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69521323.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 139042642 is about 11791.6344074942. The cubic root of 139042642 is about 518.0631125180.

The spelling of 139042642 in words is "one hundred thirty-nine million, forty-two thousand, six hundred forty-two".