21030213211 has 4 divisors (see below), whose sum is σ = 24034529392. Its totient is φ = 18025897032.

The previous prime is 21030213151. The next prime is 21030213221. The reversal of 21030213211 is 11231203012.

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 21030213211 - 2¹⁵ = 21030180443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21030213221) 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, 1502158080 + ... + 1502158093.

It is an arithmetic number, because the mean of its divisors is an integer number (6008632348).

Almost surely, 2^21030213211 is an apocalyptic number.

21030213211 is a deficient number, since it is larger than the sum of its proper divisors (3004316181).

21030213211 is an equidigital number, since it uses as much as digits as its factorization.

21030213211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3004316180.

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

Adding to 21030213211 its reverse (11231203012), we get a palindrome (32261416223).

The spelling of 21030213211 in words is "twenty-one billion, thirty million, two hundred thirteen thousand, two hundred eleven".