21210122020211 has 4 divisors (see below), whose sum is σ = 22457776256712. Its totient is φ = 19962467783712.

The previous prime is 21210122020103. The next prime is 21210122020253. The reversal of 21210122020211 is 11202022101212.

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 21210122020211 - 2³⁴ = 21192942151027 is a prime.

It is a super-2 number, since 2×21210122020211² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1247654236483 = 21210122020211 / (2 + 1 + 2 + 1 + 0 + 1 + 2 + 2 + 0 + 2 + 0 + 2 + 1 + 1).

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 21210122020211.

It is not an unprimeable number, because it can be changed into a prime (21210122020261) 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, 623827118225 + ... + 623827118258.

It is an arithmetic number, because the mean of its divisors is an integer number (5614444064178).

Almost surely, 2^{21210122020211} is an apocalyptic number.

21210122020211 is a deficient number, since it is larger than the sum of its proper divisors (1247654236501).

21210122020211 is a wasteful number, since it uses less digits than its factorization.

21210122020211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1247654236500.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21210122020211 its reverse (11202022101212), we get a palindrome (32412144121423).

The spelling of 21210122020211 in words is "twenty-one trillion, two hundred ten billion, one hundred twenty-two million, twenty thousand, two hundred eleven".