21020121233 has 8 divisors (see below), whose sum is σ = 21495770496. Its totient is φ = 20547399600.

The previous prime is 21020121229. The next prime is 21020121263. The reversal of 21020121233 is 33212102012.

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

It is a cyclic number.

It is not a de Polignac number, because 21020121233 - 2² = 21020121229 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21020121263) 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, 717383 + ... + 746108.

It is an arithmetic number, because the mean of its divisors is an integer number (2686971312).

Almost surely, 2^21020121233 is an apocalyptic number.

It is an amenable number.

21020121233 is a deficient number, since it is larger than the sum of its proper divisors (475649263).

21020121233 is a wasteful number, since it uses less digits than its factorization.

21020121233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1463815.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21020121233 its reverse (33212102012), we get a palindrome (54232223245).

The spelling of 21020121233 in words is "twenty-one billion, twenty million, one hundred twenty-one thousand, two hundred thirty-three".