21042242133 has 32 divisors (see below), whose sum is σ = 32419170432. Its totient is φ = 11998310400.

The previous prime is 21042242071. The next prime is 21042242141. The reversal of 21042242133 is 33124224012.

It is a happy number.

It is not a de Polignac number, because 21042242133 - 2²¹ = 21040144981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21042240133) by changing a digit.

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 in 31 ways as a sum of consecutive naturals, for example, 2104935 + ... + 2114907.

It is an arithmetic number, because the mean of its divisors is an integer number (1013099076).

Almost surely, 2^21042242133 is an apocalyptic number.

It is an amenable number.

21042242133 is a deficient number, since it is larger than the sum of its proper divisors (11376928299).

21042242133 is a wasteful number, since it uses less digits than its factorization.

21042242133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13765.

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21042242133 its reverse (33124224012), we get a palindrome (54166466145).

It can be divided in two parts, 21042 and 242133, that added together give a triangular number (263175 = T₇₂₅).

The spelling of 21042242133 in words is "twenty-one billion, forty-two million, two hundred forty-two thousand, one hundred thirty-three".