820169773 has 2 divisors, whose sum is σ = 820169774. Its totient is φ = 820169772.

The previous prime is 820169747. The next prime is 820169783. The reversal of 820169773 is 377961028.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 796763529 + 23406244 = 28227^2 + 4838^2 .

It is a cyclic number.

It is not a de Polignac number, because 820169773 - 2⁵ = 820169741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820169783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410084886 + 410084887.

It is an arithmetic number, because the mean of its divisors is an integer number (410084887).

Almost surely, 2^820169773 is an apocalyptic number.

It is an amenable number.

820169773 is a deficient number, since it is larger than the sum of its proper divisors (1).

820169773 is an equidigital number, since it uses as much as digits as its factorization.

820169773 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 127008, while the sum is 43.

The square root of 820169773 is about 28638.6063382980. The cubic root of 820169773 is about 936.0547537338.

The spelling of 820169773 in words is "eight hundred twenty million, one hundred sixty-nine thousand, seven hundred seventy-three".