6821054491 has 2 divisors, whose sum is σ = 6821054492. Its totient is φ = 6821054490.

The previous prime is 6821054489. The next prime is 6821054509. The reversal of 6821054491 is 1944501286.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6821054491 - 2¹ = 6821054489 is a prime.

Together with 6821054489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6821054411) 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 as a sum of consecutive naturals, namely, 3410527245 + 3410527246.

It is an arithmetic number, because the mean of its divisors is an integer number (3410527246).

Almost surely, 2^6821054491 is an apocalyptic number.

6821054491 is a deficient number, since it is larger than the sum of its proper divisors (1).

6821054491 is an equidigital number, since it uses as much as digits as its factorization.

6821054491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 6821054491 is about 82589.6754503854. The cubic root of 6821054491 is about 1896.4897784688.

The spelling of 6821054491 in words is "six billion, eight hundred twenty-one million, fifty-four thousand, four hundred ninety-one".