212211720 has 96 divisors (see below), whose sum is σ = 788224320. Its totient is φ = 48504960.

The previous prime is 212211707. The next prime is 212211733. The reversal of 212211720 is 27112212.

It is a happy number.

212211720 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (212211707) and next prime (212211733).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 212211693 and 212211702.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 39586 + ... + 44625.

It is an arithmetic number, because the mean of its divisors is an integer number (8210670).

Almost surely, 2^212211720 is an apocalyptic number.

212211720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212211720 is an abundant number, since it is smaller than the sum of its proper divisors (576012600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212211720 is a wasteful number, since it uses less digits than its factorization.

212211720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84235 (or 84228 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 212211720 is about 14567.4884588937. The cubic root of 212211720 is about 596.4716249550.

Adding to 212211720 its reverse (27112212), we get a palindrome (239323932).

The spelling of 212211720 in words is "two hundred twelve million, two hundred eleven thousand, seven hundred twenty".