993821399 has 2 divisors, whose sum is σ = 993821400. Its totient is φ = 993821398.

The previous prime is 993821393. The next prime is 993821401. The reversal of 993821399 is 993128399.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 993821399 - 2⁴ = 993821383 is a prime.

It is a super-2 number, since 2×993821399² = 1975361946220634402, which contains 22 as substring.

Together with 993821401, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 993821399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (993821393) 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, 496910699 + 496910700.

It is an arithmetic number, because the mean of its divisors is an integer number (496910700).

Almost surely, 2^993821399 is an apocalyptic number.

993821399 is a deficient number, since it is larger than the sum of its proper divisors (1).

993821399 is an equidigital number, since it uses as much as digits as its factorization.

993821399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 944784, while the sum is 53.

The square root of 993821399 is about 31524.9329737590. The cubic root of 993821399 is about 997.9362100344.

The spelling of 993821399 in words is "nine hundred ninety-three million, eight hundred twenty-one thousand, three hundred ninety-nine".