21042320433 has 8 divisors (see below), whose sum is σ = 28059282048. Its totient is φ = 14026786224.

The previous prime is 21042320347. The next prime is 21042320491. The reversal of 21042320433 is 33402324012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21042320433 - 2¹⁷ = 21042189361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21042327433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 321966 + ... + 381767.

It is an arithmetic number, because the mean of its divisors is an integer number (3507410256).

Almost surely, 2^21042320433 is an apocalyptic number.

It is an amenable number.

21042320433 is a deficient number, since it is larger than the sum of its proper divisors (7016961615).

21042320433 is an equidigital number, since it uses as much as digits as its factorization.

21042320433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 713703.

The product of its (nonzero) digits is 3456, while the sum is 24.

Adding to 21042320433 its reverse (33402324012), we get a palindrome (54444644445).

The spelling of 21042320433 in words is "twenty-one billion, forty-two million, three hundred twenty thousand, four hundred thirty-three".