21013000123211 has 4 divisors (see below), whose sum is σ = 21081446377992. Its totient is φ = 20944553868432.

The previous prime is 21013000123201. The next prime is 21013000123259. The reversal of 21013000123211 is 11232100031012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21013000123211 - 2³⁰ = 21011926381387 is a prime.

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 21013000123211.

It is not an unprimeable number, because it can be changed into a prime (21013000123201) 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, 34223126930 + ... + 34223127543.

It is an arithmetic number, because the mean of its divisors is an integer number (5270361594498).

Almost surely, 2^{21013000123211} is an apocalyptic number.

21013000123211 is a deficient number, since it is larger than the sum of its proper divisors (68446254781).

21013000123211 is an equidigital number, since it uses as much as digits as its factorization.

21013000123211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68446254780.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21013000123211 its reverse (11232100031012), we get a palindrome (32245100154223).

The spelling of 21013000123211 in words is "twenty-one trillion, thirteen billion, one hundred twenty-three thousand, two hundred eleven".