821197469 has 2 divisors, whose sum is σ = 821197470. Its totient is φ = 821197468.

The previous prime is 821197463. The next prime is 821197483. The reversal of 821197469 is 964791128.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 559890244 + 261307225 = 23662^2 + 16165^2 .

It is a cyclic number.

It is not a de Polignac number, because 821197469 - 2⁸ = 821197213 is a prime.

It is a super-2 number, since 2×821197469² = 1348730566184011922, 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 (821197463) 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 as a sum of consecutive naturals, namely, 410598734 + 410598735.

It is an arithmetic number, because the mean of its divisors is an integer number (410598735).

Almost surely, 2^821197469 is an apocalyptic number.

It is an amenable number.

821197469 is a deficient number, since it is larger than the sum of its proper divisors (1).

821197469 is an equidigital number, since it uses as much as digits as its factorization.

821197469 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 47.

The square root of 821197469 is about 28656.5432144214. The cubic root of 821197469 is about 936.4455582726.

The spelling of 821197469 in words is "eight hundred twenty-one million, one hundred ninety-seven thousand, four hundred sixty-nine".