6821813413 has 8 divisors (see below), whose sum is σ = 6996389400. Its totient is φ = 6647627520.

The previous prime is 6821813399. The next prime is 6821813419. The reversal of 6821813413 is 3143181286.

It can be written as a sum of positive squares in 4 ways, for example, as 209764 + 6821603649 = 458^2 + 82593^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6821813413 - 2²¹ = 6819716261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6821813419) 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 7 ways as a sum of consecutive naturals, for example, 61938 + ... + 132211.

It is an arithmetic number, because the mean of its divisors is an integer number (874548675).

Almost surely, 2^6821813413 is an apocalyptic number.

It is an amenable number.

6821813413 is a deficient number, since it is larger than the sum of its proper divisors (174575987).

6821813413 is a wasteful number, since it uses less digits than its factorization.

6821813413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195047.

The product of its digits is 27648, while the sum is 37.

The square root of 6821813413 is about 82594.2698557230. The cubic root of 6821813413 is about 1896.5601114084.

Adding to 6821813413 its reverse (3143181286), we get a palindrome (9964994699).

The spelling of 6821813413 in words is "six billion, eight hundred twenty-one million, eight hundred thirteen thousand, four hundred thirteen".