820633897 has 2 divisors, whose sum is σ = 820633898. Its totient is φ = 820633896.

The previous prime is 820633837. The next prime is 820633907. The reversal of 820633897 is 798336028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 815045401 + 5588496 = 28549^2 + 2364^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820633897 is a prime.

It is not a weakly prime, because it can be changed into another prime (820633837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410316948 + 410316949.

It is an arithmetic number, because the mean of its divisors is an integer number (410316949).

Almost surely, 2^820633897 is an apocalyptic number.

It is an amenable number.

820633897 is a deficient number, since it is larger than the sum of its proper divisors (1).

820633897 is an equidigital number, since it uses as much as digits as its factorization.

820633897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 435456, while the sum is 46.

The square root of 820633897 is about 28646.7083100310. The cubic root of 820633897 is about 936.2312877342.

The spelling of 820633897 in words is "eight hundred twenty million, six hundred thirty-three thousand, eight hundred ninety-seven".