210021221111 has 12 divisors (see below), whose sum is σ = 228052974960. Its totient is φ = 193325670720.

The previous prime is 210021221083. The next prime is 210021221173. The reversal of 210021221111 is 111122120012.

It is not a de Polignac number, because 210021221111 - 2³⁰ = 208947479287 is a prime.

It is a super-4 number, since 4×210021221111⁴ (a number of 46 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210021221611) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1670150 + ... + 1791491.

It is an arithmetic number, because the mean of its divisors is an integer number (19004414580).

Almost surely, 2^210021221111 is an apocalyptic number.

210021221111 is a deficient number, since it is larger than the sum of its proper divisors (18031753849).

210021221111 is a wasteful number, since it uses less digits than its factorization.

210021221111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3462026 (or 3462013 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 210021221111 its reverse (111122120012), we get a palindrome (321143341123).

The spelling of 210021221111 in words is "two hundred ten billion, twenty-one million, two hundred twenty-one thousand, one hundred eleven".