212331220 has 12 divisors (see below), whose sum is σ = 445895604. Its totient is φ = 84932480.

The previous prime is 212331211. The next prime is 212331233. The reversal of 212331220 is 22133212.

It can be written as a sum of positive squares in 2 ways, for example, as 152917956 + 59413264 = 12366^2 + 7708^2 .

It is a junction number, because it is equal to n+sod(n) for n = 212331194 and 212331203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5308261 + ... + 5308300.

It is an arithmetic number, because the mean of its divisors is an integer number (37157967).

Almost surely, 2^212331220 is an apocalyptic number.

212331220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212331220 is an abundant number, since it is smaller than the sum of its proper divisors (233564384).

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

212331220 is a wasteful number, since it uses less digits than its factorization.

212331220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10616570 (or 10616568 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 212331220 is about 14571.5894809043. The cubic root of 212331220 is about 596.5835650245.

Adding to 212331220 its reverse (22133212), we get a palindrome (234464432).

The spelling of 212331220 in words is "two hundred twelve million, three hundred thirty-one thousand, two hundred twenty".