820790099 has 2 divisors, whose sum is σ = 820790100. Its totient is φ = 820790098.

The previous prime is 820790083. The next prime is 820790183. The reversal of 820790099 is 990097028.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 820790099 - 2⁴ = 820790083 is a prime.

It is not a weakly prime, because it can be changed into another prime (820790599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410395049 + 410395050.

It is an arithmetic number, because the mean of its divisors is an integer number (410395050).

Almost surely, 2^820790099 is an apocalyptic number.

820790099 is a deficient number, since it is larger than the sum of its proper divisors (1).

820790099 is an equidigital number, since it uses as much as digits as its factorization.

820790099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81648, while the sum is 44.

The square root of 820790099 is about 28649.4345319415. The cubic root of 820790099 is about 936.2906856876.

The spelling of 820790099 in words is "eight hundred twenty million, seven hundred ninety thousand, ninety-nine".