21431423033 has 4 divisors (see below), whose sum is σ = 21431716068. Its totient is φ = 21431130000.

The previous prime is 21431423009. The next prime is 21431423047. The reversal of 21431423033 is 33032413412.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1507535929 + 19923887104 = 38827^2 + 141152^2 .

It is a cyclic number.

It is not a de Polignac number, because 21431423033 - 2⁸ = 21431422777 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21431422993 and 21431423011.

It is not an unprimeable number, because it can be changed into a prime (21431423333) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64283 + ... + 216783.

It is an arithmetic number, because the mean of its divisors is an integer number (5357929017).

Almost surely, 2^21431423033 is an apocalyptic number.

It is an amenable number.

21431423033 is a deficient number, since it is larger than the sum of its proper divisors (293035).

21431423033 is a wasteful number, since it uses less digits than its factorization.

21431423033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293034.

The product of its (nonzero) digits is 5184, while the sum is 26.

Adding to 21431423033 its reverse (33032413412), we get a palindrome (54463836445).

The spelling of 21431423033 in words is "twenty-one billion, four hundred thirty-one million, four hundred twenty-three thousand, thirty-three".