42120401242 has 4 divisors (see below), whose sum is σ = 63180601866. Its totient is φ = 21060200620.

The previous prime is 42120401231. The next prime is 42120401317. The reversal of 42120401242 is 24210402124.

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., 33276691561 + 8843709681 = 182419^2 + 94041^2 .

It is a Smith number, since the sum of its digits (22) 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 (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10530100309 + ... + 10530100312.

Almost surely, 2^42120401242 is an apocalyptic number.

42120401242 is a deficient number, since it is larger than the sum of its proper divisors (21060200624).

42120401242 is a wasteful number, since it uses less digits than its factorization.

42120401242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21060200623.

The product of its (nonzero) digits is 1024, while the sum is 22.

Adding to 42120401242 its reverse (24210402124), we get a palindrome (66330803366).

The spelling of 42120401242 in words is "forty-two billion, one hundred twenty million, four hundred one thousand, two hundred forty-two".