21143030042 has 4 divisors (see below), whose sum is σ = 31714545066. Its totient is φ = 10571515020.

The previous prime is 21143030023. The next prime is 21143030047. The reversal of 21143030042 is 24003034112.

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., 17627607361 + 3515422681 = 132769^2 + 59291^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21143029996 and 21143030023.

It is not an unprimeable number, because it can be changed into a prime (21143030047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5285757509 + ... + 5285757512.

Almost surely, 2^21143030042 is an apocalyptic number.

21143030042 is a deficient number, since it is larger than the sum of its proper divisors (10571515024).

21143030042 is a wasteful number, since it uses less digits than its factorization.

21143030042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10571515023.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21143030042 its reverse (24003034112), we get a palindrome (45146064154).

The spelling of 21143030042 in words is "twenty-one billion, one hundred forty-three million, thirty thousand, forty-two".