20775697 has 2 divisors, whose sum is σ = 20775698. Its totient is φ = 20775696.

The previous prime is 20775661. The next prime is 20775701. The reversal of 20775697 is 79657702.

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., 19501056 + 1274641 = 4416^2 + 1129^2 .

It is a cyclic number.

It is not a de Polignac number, because 20775697 - 2¹⁵ = 20742929 is a prime.

It is not a weakly prime, because it can be changed into another prime (20770697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10387848 + 10387849.

It is an arithmetic number, because the mean of its divisors is an integer number (10387849).

Almost surely, 2^20775697 is an apocalyptic number.

It is an amenable number.

20775697 is a deficient number, since it is larger than the sum of its proper divisors (1).

20775697 is an equidigital number, since it uses as much as digits as its factorization.

20775697 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 185220, while the sum is 43.

The square root of 20775697 is about 4558.0365290331. The cubic root of 20775697 is about 274.9066217398.

The spelling of 20775697 in words is "twenty million, seven hundred seventy-five thousand, six hundred ninety-seven".