6641813 has 2 divisors, whose sum is σ = 6641814. Its totient is φ = 6641812.

The previous prime is 6641809. The next prime is 6641821. The reversal of 6641813 is 3181466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5870929 + 770884 = 2423^2 + 878^2 .

It is a cyclic number.

It is not a de Polignac number, because 6641813 - 2² = 6641809 is a prime.

It is a super-2 number, since 2×6641813² = 88227359853938, which contains 22 as substring.

It is equal to p₄₅₃₈₂₇ and since 6641813 and 453827 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6641513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3320906 + 3320907.

It is an arithmetic number, because the mean of its divisors is an integer number (3320907).

Almost surely, 2^6641813 is an apocalyptic number.

It is an amenable number.

6641813 is a deficient number, since it is larger than the sum of its proper divisors (1).

6641813 is an equidigital number, since it uses as much as digits as its factorization.

6641813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 29.

The square root of 6641813 is about 2577.1715115607. The cubic root of 6641813 is about 187.9730325737.

The spelling of 6641813 in words is "six million, six hundred forty-one thousand, eight hundred thirteen".