20609559 has 28 divisors (see below), whose sum is σ = 32737536. Its totient is φ = 12923712.

The previous prime is 20609543. The next prime is 20609569. The reversal of 20609559 is 95590602.

It is not a de Polignac number, because 20609559 - 2⁴ = 20609543 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20609539) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 11562 + ... + 13224.

Almost surely, 2^20609559 is an apocalyptic number.

20609559 is a deficient number, since it is larger than the sum of its proper divisors (12127977).

20609559 is an equidigital number, since it uses as much as digits as its factorization.

20609559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698 (or 1683 counting only the distinct ones).

The product of its (nonzero) digits is 24300, while the sum is 36.

The square root of 20609559 is about 4539.7752146995. The cubic root of 20609559 is about 274.1718734467.

The spelling of 20609559 in words is "twenty million, six hundred nine thousand, five hundred fifty-nine".