20235609 has 8 divisors (see below), whose sum is σ = 29978720. Its totient is φ = 13490388.

The previous prime is 20235599. The next prime is 20235617. The reversal of 20235609 is 90653202.

20235609 is a `hidden beast` number, since 20 + 2 + 35 + 609 = 666.

It is not a de Polignac number, because 20235609 - 2⁸ = 20235353 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 749467 = 20235609 / (2 + 0 + 2 + 3 + 5 + 6 + 0 + 9).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20235629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 374707 + ... + 374760.

It is an arithmetic number, because the mean of its divisors is an integer number (3747340).

Almost surely, 2^20235609 is an apocalyptic number.

It is an amenable number.

20235609 is a deficient number, since it is larger than the sum of its proper divisors (9743111).

20235609 is an equidigital number, since it uses as much as digits as its factorization.

20235609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 749476 (or 749470 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 20235609 is about 4498.4007158100. The cubic root of 20235609 is about 272.5035052715.

The spelling of 20235609 in words is "twenty million, two hundred thirty-five thousand, six hundred nine".