21323033321 has 4 divisors (see below), whose sum is σ = 21324118272. Its totient is φ = 21321948372.

The previous prime is 21323033267. The next prime is 21323033327. The reversal of 21323033321 is 12333032312.

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 a de Polignac number, because none of the positive numbers 2^k-21323033321 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 (21323033327) 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, 512441 + ... + 552486.

It is an arithmetic number, because the mean of its divisors is an integer number (5331029568).

Almost surely, 2^21323033321 is an apocalyptic number.

It is an amenable number.

21323033321 is a deficient number, since it is larger than the sum of its proper divisors (1084951).

21323033321 is a wasteful number, since it uses less digits than its factorization.

21323033321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1084950.

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

Adding to 21323033321 its reverse (12333032312), we get a palindrome (33656065633).

The spelling of 21323033321 in words is "twenty-one billion, three hundred twenty-three million, thirty-three thousand, three hundred twenty-one".