21120240133 has 4 divisors (see below), whose sum is σ = 21204384768. Its totient is φ = 21036095500.

The previous prime is 21120240121. The next prime is 21120240181. The reversal of 21120240133 is 33104202112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21120240133 - 2¹³ = 21120231941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21120240133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120247133) 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 3 ways as a sum of consecutive naturals, for example, 42071941 + ... + 42072442.

It is an arithmetic number, because the mean of its divisors is an integer number (5301096192).

Almost surely, 2^21120240133 is an apocalyptic number.

It is an amenable number.

21120240133 is a deficient number, since it is larger than the sum of its proper divisors (84144635).

21120240133 is an equidigital number, since it uses as much as digits as its factorization.

21120240133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84144634.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21120240133 its reverse (33104202112), we get a palindrome (54224442245).

The spelling of 21120240133 in words is "twenty-one billion, one hundred twenty million, two hundred forty thousand, one hundred thirty-three".