211806220156 has 24 divisors (see below), whose sum is σ = 389165328720. Its totient is φ = 100725136512.

The previous prime is 211806220147. The next prime is 211806220163. The reversal of 211806220156 is 651022608112.

It is a happy number.

211806220156 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 13618465 + ... + 13634008.

It is an arithmetic number, because the mean of its divisors is an integer number (16215222030).

Almost surely, 2^211806220156 is an apocalyptic number.

It is an amenable number.

211806220156 is a deficient number, since it is larger than the sum of its proper divisors (177359108564).

211806220156 is a wasteful number, since it uses less digits than its factorization.

211806220156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27252573 (or 27252571 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

Adding to 211806220156 its reverse (651022608112), we get a palindrome (862828828268).

The spelling of 211806220156 in words is "two hundred eleven billion, eight hundred six million, two hundred twenty thousand, one hundred fifty-six".