21201301321 has 4 divisors (see below), whose sum is σ = 21399444432. Its totient is φ = 21003158212.

The previous prime is 21201301313. The next prime is 21201301327. The reversal of 21201301321 is 12310310212.

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 not a de Polignac number, because 21201301321 - 2³ = 21201301313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201301295 and 21201301304.

It is not an unprimeable number, because it can be changed into a prime (21201301327) 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, 99071395 + ... + 99071608.

It is an arithmetic number, because the mean of its divisors is an integer number (5349861108).

Almost surely, 2^21201301321 is an apocalyptic number.

It is an amenable number.

21201301321 is a deficient number, since it is larger than the sum of its proper divisors (198143111).

21201301321 is a wasteful number, since it uses less digits than its factorization.

21201301321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198143110.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21201301321 its reverse (12310310212), we get a palindrome (33511611533).

The spelling of 21201301321 in words is "twenty-one billion, two hundred one million, three hundred one thousand, three hundred twenty-one".