20213563 has 2 divisors, whose sum is σ = 20213564. Its totient is φ = 20213562.

The previous prime is 20213503. The next prime is 20213603. The reversal of 20213563 is 36531202.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20213563 - 2¹³ = 20205371 is a prime.

It is not a weakly prime, because it can be changed into another prime (20213503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10106781 + 10106782.

It is an arithmetic number, because the mean of its divisors is an integer number (10106782).

Almost surely, 2^20213563 is an apocalyptic number.

20213563 is a deficient number, since it is larger than the sum of its proper divisors (1).

20213563 is an equidigital number, since it uses as much as digits as its factorization.

20213563 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 22.

The square root of 20213563 is about 4495.9496216039. The cubic root of 20213563 is about 272.4045082461.

Adding to 20213563 its reverse (36531202), we get a palindrome (56744765).

The spelling of 20213563 in words is "twenty million, two hundred thirteen thousand, five hundred sixty-three".