21221132329 has 4 divisors (see below), whose sum is σ = 21794676484. Its totient is φ = 20647588176.

The previous prime is 21221132327. The next prime is 21221132369. The reversal of 21221132329 is 92323112212.

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 9806346729 + 11414785600 = 99027^2 + 106840^2 .

It is a cyclic number.

It is not a de Polignac number, because 21221132329 - 2¹ = 21221132327 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221132297 and 21221132306.

It is not an unprimeable number, because it can be changed into a prime (21221132323) 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, 286772022 + ... + 286772095.

It is an arithmetic number, because the mean of its divisors is an integer number (5448669121).

Almost surely, 2^21221132329 is an apocalyptic number.

It is an amenable number.

21221132329 is a deficient number, since it is larger than the sum of its proper divisors (573544155).

21221132329 is an equidigital number, since it uses as much as digits as its factorization.

21221132329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573544154.

The product of its digits is 2592, while the sum is 28.

The spelling of 21221132329 in words is "twenty-one billion, two hundred twenty-one million, one hundred thirty-two thousand, three hundred twenty-nine".