20563399 has 2 divisors, whose sum is σ = 20563400. Its totient is φ = 20563398.

The previous prime is 20563391. The next prime is 20563457. The reversal of 20563399 is 99336502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20563399 - 2³ = 20563391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20563391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10281699 + 10281700.

It is an arithmetic number, because the mean of its divisors is an integer number (10281700).

Almost surely, 2^20563399 is an apocalyptic number.

20563399 is a deficient number, since it is larger than the sum of its proper divisors (1).

20563399 is an equidigital number, since it uses as much as digits as its factorization.

20563399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43740, while the sum is 37.

The square root of 20563399 is about 4534.6884126696. The cubic root of 20563399 is about 273.9670294389.

The spelling of 20563399 in words is "twenty million, five hundred sixty-three thousand, three hundred ninety-nine".