20238665 has 12 divisors (see below), whose sum is σ = 25157964. Its totient is φ = 15629376.

The previous prime is 20238661. The next prime is 20238671. The reversal of 20238665 is 56683202.

It can be written as a sum of positive squares in 6 ways, for example, as 141376 + 20097289 = 376^2 + 4483^2 .

It is not a de Polignac number, because 20238665 - 2² = 20238661 is a prime.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20238661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1799 + ... + 6611.

It is an arithmetic number, because the mean of its divisors is an integer number (2096497).

Almost surely, 2^20238665 is an apocalyptic number.

It is an amenable number.

20238665 is a deficient number, since it is larger than the sum of its proper divisors (4919299).

20238665 is an equidigital number, since it uses as much as digits as its factorization.

20238665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4876 (or 4847 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 20238665 is about 4498.7403792617. The cubic root of 20238665 is about 272.5172224897.

The spelling of 20238665 in words is "twenty million, two hundred thirty-eight thousand, six hundred sixty-five".