213121121313 has 4 divisors (see below), whose sum is σ = 284161495088. Its totient is φ = 142080747540.

The previous prime is 213121121309. The next prime is 213121121341. The reversal of 213121121313 is 313121121312.

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 not a de Polignac number, because 213121121313 - 2² = 213121121309 is a prime.

It is a super-2 number, since 2×213121121313² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 213121121313.

It is not an unprimeable number, because it can be changed into a prime (213121121393) 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, 35520186883 + ... + 35520186888.

It is an arithmetic number, because the mean of its divisors is an integer number (71040373772).

Almost surely, 2^213121121313 is an apocalyptic number.

It is an amenable number.

213121121313 is a deficient number, since it is larger than the sum of its proper divisors (71040373775).

213121121313 is an equidigital number, since it uses as much as digits as its factorization.

213121121313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71040373774.

The product of its digits is 216, while the sum is 21.

Adding to 213121121313 its reverse (313121121312), we get a palindrome (526242242625).

Subtracting 213121121313 from its reverse (313121121312), we obtain a palindrome (99999999999).

The spelling of 213121121313 in words is "two hundred thirteen billion, one hundred twenty-one million, one hundred twenty-one thousand, three hundred thirteen".