213221412 has 36 divisors (see below), whose sum is σ = 570682476. Its totient is φ = 66892800.

The previous prime is 213221389. The next prime is 213221419. The reversal of 213221412 is 214122312.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 75064896 + 138156516 = 8664^2 + 11754^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (213221419) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 173589 + ... + 174812.

It is an arithmetic number, because the mean of its divisors is an integer number (15852291).

Almost surely, 2^213221412 is an apocalyptic number.

It is an amenable number.

213221412 is an abundant number, since it is smaller than the sum of its proper divisors (357461064).

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

213221412 is a wasteful number, since it uses less digits than its factorization.

213221412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348428 (or 348423 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 213221412 is about 14602.1029992258. The cubic root of 213221412 is about 597.4161219301.

Adding to 213221412 its reverse (214122312), we get a palindrome (427343724).

The spelling of 213221412 in words is "two hundred thirteen million, two hundred twenty-one thousand, four hundred twelve".