20641085 has 4 divisors (see below), whose sum is σ = 24769308. Its totient is φ = 16512864.

The previous prime is 20641073. The next prime is 20641099. The reversal of 20641085 is 58014602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4108729 + 16532356 = 2027^2 + 4066^2 .

It is a cyclic number.

It is not a de Polignac number, because 20641085 - 2¹⁴ = 20624701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2064104 + ... + 2064113.

It is an arithmetic number, because the mean of its divisors is an integer number (6192327).

Almost surely, 2^20641085 is an apocalyptic number.

It is an amenable number.

20641085 is a deficient number, since it is larger than the sum of its proper divisors (4128223).

20641085 is an equidigital number, since it uses as much as digits as its factorization.

20641085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4128222.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20641085 is about 4543.2460862251. The cubic root of 20641085 is about 274.3116005015.

Adding to 20641085 its reverse (58014602), we get a palindrome (78655687).

The spelling of 20641085 in words is "twenty million, six hundred forty-one thousand, eighty-five".