21000212211 has 24 divisors (see below), whose sum is σ = 31393704384. Its totient is φ = 12383390880.

The previous prime is 21000212143. The next prime is 21000212239. The reversal of 21000212211 is 11221200012.

It is not a de Polignac number, because 21000212211 - 2⁷ = 21000212083 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000212291) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 187245 + ... + 277598.

It is an arithmetic number, because the mean of its divisors is an integer number (1308071016).

Almost surely, 2^21000212211 is an apocalyptic number.

21000212211 is a deficient number, since it is larger than the sum of its proper divisors (10393492173).

21000212211 is a wasteful number, since it uses less digits than its factorization.

21000212211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 464931 (or 464894 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21000212211 its reverse (11221200012), we get a palindrome (32221412223).

The spelling of 21000212211 in words is "twenty-one billion, two hundred twelve thousand, two hundred eleven".