20660889 has 4 divisors (see below), whose sum is σ = 27547856. Its totient is φ = 13773924.

The previous prime is 20660881. The next prime is 20660897. The reversal of 20660889 is 98806602.

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 an interprime number because it is at equal distance from previous prime (20660881) and next prime (20660897).

It is not a de Polignac number, because 20660889 - 2³ = 20660881 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20660881) 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, 3443479 + ... + 3443484.

It is an arithmetic number, because the mean of its divisors is an integer number (6886964).

Almost surely, 2^20660889 is an apocalyptic number.

It is an amenable number.

20660889 is a deficient number, since it is larger than the sum of its proper divisors (6886967).

20660889 is an equidigital number, since it uses as much as digits as its factorization.

20660889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6886966.

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 20660889 is about 4545.4250626317. The cubic root of 20660889 is about 274.3993014868.

The spelling of 20660889 in words is "twenty million, six hundred sixty thousand, eight hundred eighty-nine".