13213109821 has 2 divisors, whose sum is σ = 13213109822. Its totient is φ = 13213109820.

The previous prime is 13213109807. The next prime is 13213109857. The reversal of 13213109821 is 12890131231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13198563225 + 14546596 = 114885^2 + 3814^2 .

It is an emirp because it is prime and its reverse (12890131231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13213109821 - 2²⁹ = 12676238909 is a prime.

It is a super-2 number, since 2×13213109821² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13213106821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6606554910 + 6606554911.

It is an arithmetic number, because the mean of its divisors is an integer number (6606554911).

Almost surely, 2^13213109821 is an apocalyptic number.

It is an amenable number.

13213109821 is a deficient number, since it is larger than the sum of its proper divisors (1).

13213109821 is an equidigital number, since it uses as much as digits as its factorization.

13213109821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 31.

The spelling of 13213109821 in words is "thirteen billion, two hundred thirteen million, one hundred nine thousand, eight hundred twenty-one".