20663489 has 16 divisors (see below), whose sum is σ = 26027136. Its totient is φ = 15936000.

The previous prime is 20663473. The next prime is 20663491. The reversal of 20663489 is 98436602.

It is a cyclic number.

It is not a de Polignac number, because 20663489 - 2⁴ = 20663473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20663189) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6449 + ... + 9105.

It is an arithmetic number, because the mean of its divisors is an integer number (1626696).

Almost surely, 2^20663489 is an apocalyptic number.

It is an amenable number.

20663489 is a deficient number, since it is larger than the sum of its proper divisors (5363647).

20663489 is a wasteful number, since it uses less digits than its factorization.

20663489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2776.

The product of its (nonzero) digits is 62208, while the sum is 38.

The square root of 20663489 is about 4545.7110554896. The cubic root of 20663489 is about 274.4108112894.

It can be divided in two parts, 2066 and 3489, that added together give a palindrome (5555).

The spelling of 20663489 in words is "twenty million, six hundred sixty-three thousand, four hundred eighty-nine".