21033101321 has 2 divisors, whose sum is σ = 21033101322. Its totient is φ = 21033101320.

The previous prime is 21033101291. The next prime is 21033101333. The reversal of 21033101321 is 12310133012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20573599225 + 459502096 = 143435^2 + 21436^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033101321 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21033101321.

It is not a weakly prime, because it can be changed into another prime (21033101351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516550660 + 10516550661.

It is an arithmetic number, because the mean of its divisors is an integer number (10516550661).

Almost surely, 2^21033101321 is an apocalyptic number.

It is an amenable number.

21033101321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033101321 is an equidigital number, since it uses as much as digits as its factorization.

21033101321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21033101321 its reverse (12310133012), we get a palindrome (33343234333).

The spelling of 21033101321 in words is "twenty-one billion, thirty-three million, one hundred one thousand, three hundred twenty-one".