821290919 has 2 divisors, whose sum is σ = 821290920. Its totient is φ = 821290918.

The previous prime is 821290913. The next prime is 821290957. The reversal of 821290919 is 919092128.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 821290919 - 2⁸ = 821290663 is a prime.

It is a super-2 number, since 2×821290919² = 1349037547263729122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821290913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410645459 + 410645460.

It is an arithmetic number, because the mean of its divisors is an integer number (410645460).

Almost surely, 2^821290919 is an apocalyptic number.

821290919 is a deficient number, since it is larger than the sum of its proper divisors (1).

821290919 is an equidigital number, since it uses as much as digits as its factorization.

821290919 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 821290919 is about 28658.1736857044. The cubic root of 821290919 is about 936.4810785632.

The spelling of 821290919 in words is "eight hundred twenty-one million, two hundred ninety thousand, nine hundred nineteen".