1020004042 has 4 divisors (see below), whose sum is σ = 1530006066. Its totient is φ = 510002020.

The previous prime is 1020004033. The next prime is 1020004043. The reversal of 1020004042 is 2404000201.

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., 792929281 + 227074761 = 28159^2 + 15069^2 .

It is a Smith number, since the sum of its digits (13) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1020004043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255001009 + ... + 255001012.

Almost surely, 2^1020004042 is an apocalyptic number.

1020004042 is a deficient number, since it is larger than the sum of its proper divisors (510002024).

1020004042 is an equidigital number, since it uses as much as digits as its factorization.

1020004042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510002023.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 1020004042 is about 31937.5021252445. The cubic root of 1020004042 is about 1006.6240392214.

Adding to 1020004042 its reverse (2404000201), we get a palindrome (3424004243).

The spelling of 1020004042 in words is "one billion, twenty million, four thousand, forty-two".