820142369 has 2 divisors, whose sum is σ = 820142370. Its totient is φ = 820142368.

The previous prime is 820142347. The next prime is 820142381. The reversal of 820142369 is 963241028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 420742144 + 399400225 = 20512^2 + 19985^2 .

It is a cyclic number.

It is not a de Polignac number, because 820142369 - 2¹² = 820138273 is a prime.

It is a super-2 number, since 2×820142369² = 1345267010857864322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (820142969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410071184 + 410071185.

It is an arithmetic number, because the mean of its divisors is an integer number (410071185).

Almost surely, 2^820142369 is an apocalyptic number.

It is an amenable number.

820142369 is a deficient number, since it is larger than the sum of its proper divisors (1).

820142369 is an equidigital number, since it uses as much as digits as its factorization.

820142369 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 820142369 is about 28638.1278892319. The cubic root of 820142369 is about 936.0443282784.

The spelling of 820142369 in words is "eight hundred twenty million, one hundred forty-two thousand, three hundred sixty-nine".