20163553 has 4 divisors (see below), whose sum is σ = 20180160. Its totient is φ = 20146948.

The previous prime is 20163551. The next prime is 20163593. The reversal of 20163553 is 35536102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20163553 - 2¹ = 20163551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20163551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6325 + ... + 8962.

It is an arithmetic number, because the mean of its divisors is an integer number (5045040).

Almost surely, 2^20163553 is an apocalyptic number.

It is an amenable number.

20163553 is a deficient number, since it is larger than the sum of its proper divisors (16607).

20163553 is a wasteful number, since it uses less digits than its factorization.

20163553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16606.

The product of its (nonzero) digits is 2700, while the sum is 25.

The square root of 20163553 is about 4490.3845046944. The cubic root of 20163553 is about 272.1796724154.

Adding to 20163553 its reverse (35536102), we get a palindrome (55699655).

The spelling of 20163553 in words is "twenty million, one hundred sixty-three thousand, five hundred fifty-three".