6821386490 has 8 divisors (see below), whose sum is σ = 12278495700. Its totient is φ = 2728554592.

The previous prime is 6821386487. The next prime is 6821386499. The reversal of 6821386490 is 946831286.

It can be written as a sum of positive squares in 2 ways, for example, as 5964009529 + 857376961 = 77227^2 + 29281^2 .

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

It is not an unprimeable number, because it can be changed into a prime (6821386499) 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, 341069315 + ... + 341069334.

Almost surely, 2^6821386490 is an apocalyptic number.

6821386490 is a deficient number, since it is larger than the sum of its proper divisors (5457109210).

6821386490 is a wasteful number, since it uses less digits than its factorization.

6821386490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 682138656.

The product of its (nonzero) digits is 497664, while the sum is 47.

The square root of 6821386490 is about 82591.6853563360. The cubic root of 6821386490 is about 1896.5205470494.

The spelling of 6821386490 in words is "six billion, eight hundred twenty-one million, three hundred eighty-six thousand, four hundred ninety".