20565737 has 2 divisors, whose sum is σ = 20565738. Its totient is φ = 20565736.

The previous prime is 20565731. The next prime is 20565751. The reversal of 20565737 is 73756502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15085456 + 5480281 = 3884^2 + 2341^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20565737 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20565697 and 20565706.

It is not a weakly prime, because it can be changed into another prime (20565731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10282868 + 10282869.

It is an arithmetic number, because the mean of its divisors is an integer number (10282869).

Almost surely, 2^20565737 is an apocalyptic number.

It is an amenable number.

20565737 is a deficient number, since it is larger than the sum of its proper divisors (1).

20565737 is an equidigital number, since it uses as much as digits as its factorization.

20565737 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 44100, while the sum is 35.

The square root of 20565737 is about 4534.9461959322. The cubic root of 20565737 is about 273.9774121362.

The spelling of 20565737 in words is "twenty million, five hundred sixty-five thousand, seven hundred thirty-seven".