20043553 has 6 divisors (see below), whose sum is σ = 20759414. Its totient is φ = 19351584.

The previous prime is 20043469. The next prime is 20043559. The reversal of 20043553 is 35534002.

It can be written as a sum of positive squares in 3 ways, for example, as 7033104 + 13010449 = 2652^2 + 3607^2 .

It is not a de Polignac number, because 20043553 - 2¹⁷ = 19912481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20043559) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11076 + ... + 12757.

Almost surely, 2^20043553 is an apocalyptic number.

It is an amenable number.

20043553 is a deficient number, since it is larger than the sum of its proper divisors (715861).

20043553 is an equidigital number, since it uses as much as digits as its factorization.

20043553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23891 (or 23862 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 22.

The square root of 20043553 is about 4477.0026803655. The cubic root of 20043553 is about 271.6386538586.

Adding to 20043553 its reverse (35534002), we get a palindrome (55577555).

The spelling of 20043553 in words is "twenty million, forty-three thousand, five hundred fifty-three".