213440444 has 12 divisors (see below), whose sum is σ = 426880944. Its totient is φ = 91474464.

The previous prime is 213440441. The next prime is 213440453. The reversal of 213440444 is 444044312.

It is a happy number.

213440444 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213440441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3811409 + ... + 3811464.

It is an arithmetic number, because the mean of its divisors is an integer number (35573412).

Almost surely, 2^213440444 is an apocalyptic number.

It is an amenable number.

213440444 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

213440444 is a wasteful number, since it uses less digits than its factorization.

213440444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7622884 (or 7622882 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 26.

The square root of 213440444 is about 14609.6010896944. The cubic root of 213440444 is about 597.6206174448.

Adding to 213440444 its reverse (444044312), we get a palindrome (657484756).

The spelling of 213440444 in words is "two hundred thirteen million, four hundred forty thousand, four hundred forty-four".