212220144 has 120 divisors (see below), whose sum is σ = 622393200. Its totient is φ = 67415040.

The previous prime is 212220143. The next prime is 212220157. The reversal of 212220144 is 441022212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212220143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 371379 + ... + 371949.

It is an arithmetic number, because the mean of its divisors is an integer number (5186610).

Almost surely, 2^212220144 is an apocalyptic number.

212220144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212220144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311196600).

212220144 is an abundant number, since it is smaller than the sum of its proper divisors (410173056).

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

212220144 is a wasteful number, since it uses less digits than its factorization.

212220144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703 (or 694 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 212220144 is about 14567.7775930304. Note that the first 3 decimals coincide. The cubic root of 212220144 is about 596.4795174040.

Adding to 212220144 its reverse (441022212), we get a palindrome (653242356).

The spelling of 212220144 in words is "two hundred twelve million, two hundred twenty thousand, one hundred forty-four".