21432101321 has 4 divisors (see below), whose sum is σ = 21521031444. Its totient is φ = 21343171200.

The previous prime is 21432101279. The next prime is 21432101357. The reversal of 21432101321 is 12310123412.

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 15726414025 + 5705687296 = 125405^2 + 75536^2 .

It is a cyclic number.

It is not a de Polignac number, because 21432101321 - 2³⁴ = 4252232137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21432101293 and 21432101302.

It is not an unprimeable number, because it can be changed into a prime (21432104321) 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, 44464700 + ... + 44465181.

It is an arithmetic number, because the mean of its divisors is an integer number (5380257861).

Almost surely, 2^21432101321 is an apocalyptic number.

It is an amenable number.

21432101321 is a deficient number, since it is larger than the sum of its proper divisors (88930123).

21432101321 is an equidigital number, since it uses as much as digits as its factorization.

21432101321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88930122.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21432101321 its reverse (12310123412), we get a palindrome (33742224733).

The spelling of 21432101321 in words is "twenty-one billion, four hundred thirty-two million, one hundred one thousand, three hundred twenty-one".