42400042 has 4 divisors (see below), whose sum is σ = 63600066. Its totient is φ = 21200020.

The previous prime is 42400009. The next prime is 42400067. The reversal of 42400042 is 24000424.

42400042 is digitally balanced in base 2, 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., 40182921 + 2217121 = 6339^2 + 1489^2 .

It is a junction number, because it is equal to n+sod(n) for n = 42399989 and 42400025.

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, 10600009 + ... + 10600012.

Almost surely, 2^42400042 is an apocalyptic number.

42400042 is a deficient number, since it is larger than the sum of its proper divisors (21200024).

42400042 is a wasteful number, since it uses less digits than its factorization.

42400042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21200023.

The product of its (nonzero) digits is 256, while the sum is 16.

The square root of 42400042 is about 6511.5314634884. The cubic root of 42400042 is about 348.7027953907.

Adding to 42400042 its reverse (24000424), we get a palindrome (66400466).

The spelling of 42400042 in words is "forty-two million, four hundred thousand, forty-two".