21132021233 has 24 divisors (see below), whose sum is σ = 22183177464. Its totient is φ = 20113920000.

The previous prime is 21132021187. The next prime is 21132021289. The reversal of 21132021233 is 33212023112.

It can be written as a sum of positive squares in 12 ways, for example, as 1440354304 + 19691666929 = 37952^2 + 140327^2 .

It is not a de Polignac number, because 21132021233 - 2¹⁰ = 21132020209 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 (21132023233) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35161133 + ... + 35161733.

It is an arithmetic number, because the mean of its divisors is an integer number (924299061).

Almost surely, 2^21132021233 is an apocalyptic number.

It is an amenable number.

21132021233 is a deficient number, since it is larger than the sum of its proper divisors (1051156231).

21132021233 is an equidigital number, since it uses as much as digits as its factorization.

21132021233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 933 (or 836 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21132021233 its reverse (33212023112), we get a palindrome (54344044345).

The spelling of 21132021233 in words is "twenty-one billion, one hundred thirty-two million, twenty-one thousand, two hundred thirty-three".