20656489 has 8 divisors (see below), whose sum is σ = 24089600. Its totient is φ = 17705268.

The previous prime is 20656483. The next prime is 20656499. The reversal of 20656489 is 98465602.

It is a happy number.

It is not a de Polignac number, because 20656489 - 2¹¹ = 20654441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20656483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29769 + ... + 30454.

It is an arithmetic number, because the mean of its divisors is an integer number (3011200).

Almost surely, 2^20656489 is an apocalyptic number.

It is an amenable number.

20656489 is a deficient number, since it is larger than the sum of its proper divisors (3433111).

20656489 is an frugal number, since it uses more digits than its factorization.

20656489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60244 (or 60230 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 20656489 is about 4544.9410337209. The cubic root of 20656489 is about 274.3798211595.

The spelling of 20656489 in words is "twenty million, six hundred fifty-six thousand, four hundred eighty-nine".