211220212109 has 16 divisors (see below), whose sum is σ = 223298726400. Its totient is φ = 199385362176.

The previous prime is 211220212067. The next prime is 211220212117. The reversal of 211220212109 is 901212022112.

211220212109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 211220212109 - 2¹⁶ = 211220146573 is a prime.

It is a super-2 number, since 2×211220212109² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211220212199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3994757 + ... + 4047285.

It is an arithmetic number, because the mean of its divisors is an integer number (13956170400).

Almost surely, 2^211220212109 is an apocalyptic number.

It is an amenable number.

211220212109 is a deficient number, since it is larger than the sum of its proper divisors (12078514291).

211220212109 is a wasteful number, since it uses less digits than its factorization.

211220212109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54844.

The product of its (nonzero) digits is 288, while the sum is 23.

The spelling of 211220212109 in words is "two hundred eleven billion, two hundred twenty million, two hundred twelve thousand, one hundred nine".