20820363569 has 2 divisors, whose sum is σ = 20820363570. Its totient is φ = 20820363568.

The previous prime is 20820363521. The next prime is 20820363581. The reversal of 20820363569 is 96536302802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19428178225 + 1392185344 = 139385^2 + 37312^2 .

It is a cyclic number.

It is not a de Polignac number, because 20820363569 - 2³² = 16525396273 is a prime.

It is a super-2 number, since 2×20820363569² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20820363589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10410181784 + 10410181785.

It is an arithmetic number, because the mean of its divisors is an integer number (10410181785).

Almost surely, 2^20820363569 is an apocalyptic number.

It is an amenable number.

20820363569 is a deficient number, since it is larger than the sum of its proper divisors (1).

20820363569 is an equidigital number, since it uses as much as digits as its factorization.

20820363569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 466560, while the sum is 44.

The spelling of 20820363569 in words is "twenty billion, eight hundred twenty million, three hundred sixty-three thousand, five hundred sixty-nine".