213440660 has 12 divisors (see below), whose sum is σ = 448225428. Its totient is φ = 85376256.

The previous prime is 213440641. The next prime is 213440683. The reversal of 213440660 is 66044312.

It can be written as a sum of positive squares in 2 ways, for example, as 117635716 + 95804944 = 10846^2 + 9788^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 5335997 + ... + 5336036.

It is an arithmetic number, because the mean of its divisors is an integer number (37352119).

Almost surely, 2^213440660 is an apocalyptic number.

213440660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213440660 is an abundant number, since it is smaller than the sum of its proper divisors (234784768).

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

213440660 is a wasteful number, since it uses less digits than its factorization.

213440660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10672042 (or 10672040 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 213440660 is about 14609.6084820915. The cubic root of 213440660 is about 597.6208190405.

Adding to 213440660 its reverse (66044312), we get a palindrome (279484972).

The spelling of 213440660 in words is "two hundred thirteen million, four hundred forty thousand, six hundred sixty".