821393113 has 2 divisors, whose sum is σ = 821393114. Its totient is φ = 821393112.

The previous prime is 821393093. The next prime is 821393119. The reversal of 821393113 is 311393128.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 541399824 + 279993289 = 23268^2 + 16733^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-821393113 is a prime.

It is not a weakly prime, because it can be changed into another prime (821393119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410696556 + 410696557.

It is an arithmetic number, because the mean of its divisors is an integer number (410696557).

Almost surely, 2^821393113 is an apocalyptic number.

It is an amenable number.

821393113 is a deficient number, since it is larger than the sum of its proper divisors (1).

821393113 is an equidigital number, since it uses as much as digits as its factorization.

821393113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 31.

The square root of 821393113 is about 28659.9566119699. The cubic root of 821393113 is about 936.5199193588.

The spelling of 821393113 in words is "eight hundred twenty-one million, three hundred ninety-three thousand, one hundred thirteen".