20457563 has 4 divisors (see below), whose sum is σ = 23380080. Its totient is φ = 17535048.

The previous prime is 20457533. The next prime is 20457583. The reversal of 20457563 is 36575402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20457563 is a prime.

It is a super-3 number, since 3×20457563³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20457533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1461248 + ... + 1461261.

It is an arithmetic number, because the mean of its divisors is an integer number (5845020).

Almost surely, 2^20457563 is an apocalyptic number.

20457563 is a deficient number, since it is larger than the sum of its proper divisors (2922517).

20457563 is an equidigital number, since it uses as much as digits as its factorization.

20457563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2922516.

The product of its (nonzero) digits is 25200, while the sum is 32.

The square root of 20457563 is about 4523.0037585658. The cubic root of 20457563 is about 273.4962015989.

The spelling of 20457563 in words is "twenty million, four hundred fifty-seven thousand, five hundred sixty-three".