6641213 has 4 divisors (see below), whose sum is σ = 6646428. Its totient is φ = 6636000.

The previous prime is 6641197. The next prime is 6641231. The reversal of 6641213 is 3121466.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3121466 = 2 ⋅1560733.

It can be written as a sum of positive squares in 2 ways, for example, as 5555449 + 1085764 = 2357^2 + 1042^2 .

It is a cyclic number.

It is not a de Polignac number, because 6641213 - 2⁴ = 6641197 is a prime.

It is a super-2 number, since 2×6641213² = 88211420222738, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6641263) 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 3 ways as a sum of consecutive naturals, for example, 713 + ... + 3713.

It is an arithmetic number, because the mean of its divisors is an integer number (1661607).

Almost surely, 2^6641213 is an apocalyptic number.

It is an amenable number.

6641213 is a deficient number, since it is larger than the sum of its proper divisors (5215).

6641213 is a wasteful number, since it uses less digits than its factorization.

6641213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5214.

The product of its digits is 864, while the sum is 23.

The square root of 6641213 is about 2577.0551022436. The cubic root of 6641213 is about 187.9673721104.

Subtracting from 6641213 its sum of digits (23), we obtain a triangular number (6641190 = T₃₆₄₄).

Adding to 6641213 its reverse (3121466), we get a palindrome (9762679).

The spelling of 6641213 in words is "six million, six hundred forty-one thousand, two hundred thirteen".