21123332033 has 4 divisors (see below), whose sum is σ = 21317124180. Its totient is φ = 20929539888.

The previous prime is 21123331993. The next prime is 21123332039. The reversal of 21123332033 is 33023332112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8421365824 + 12701966209 = 91768^2 + 112703^2 .

It is a cyclic number.

It is not a de Polignac number, because 21123332033 - 2⁶ = 21123331969 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21123332039) 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, 96895910 + ... + 96896127.

It is an arithmetic number, because the mean of its divisors is an integer number (5329281045).

Almost surely, 2^21123332033 is an apocalyptic number.

It is an amenable number.

21123332033 is a deficient number, since it is larger than the sum of its proper divisors (193792147).

21123332033 is a wasteful number, since it uses less digits than its factorization.

21123332033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193792146.

The product of its (nonzero) digits is 1944, while the sum is 23.

Adding to 21123332033 its reverse (33023332112), we get a palindrome (54146664145).

The spelling of 21123332033 in words is "twenty-one billion, one hundred twenty-three million, three hundred thirty-two thousand, thirty-three".