820899637 has 2 divisors, whose sum is σ = 820899638. Its totient is φ = 820899636.

The previous prime is 820899539. The next prime is 820899641. The reversal of 820899637 is 736998028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 751527396 + 69372241 = 27414^2 + 8329^2 .

It is a cyclic number.

It is not a de Polignac number, because 820899637 - 2¹⁵ = 820866869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820899337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410449818 + 410449819.

It is an arithmetic number, because the mean of its divisors is an integer number (410449819).

Almost surely, 2^820899637 is an apocalyptic number.

It is an amenable number.

820899637 is a deficient number, since it is larger than the sum of its proper divisors (1).

820899637 is an equidigital number, since it uses as much as digits as its factorization.

820899637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1306368, while the sum is 52.

The square root of 820899637 is about 28651.3461638367. The cubic root of 820899637 is about 936.3323345198.

The spelling of 820899637 in words is "eight hundred twenty million, eight hundred ninety-nine thousand, six hundred thirty-seven".