20409085 has 8 divisors (see below), whose sum is σ = 24593976. Its totient is φ = 16258560.

The previous prime is 20409079. The next prime is 20409107. The reversal of 20409085 is 58090402.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2752281 + 17656804 = 1659^2 + 4202^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20409085 - 2⁷ = 20408957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7264 + ... + 9673.

It is an arithmetic number, because the mean of its divisors is an integer number (3074247).

Almost surely, 2^20409085 is an apocalyptic number.

It is an amenable number.

20409085 is a deficient number, since it is larger than the sum of its proper divisors (4184891).

20409085 is a wasteful number, since it uses less digits than its factorization.

20409085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17183.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 20409085 is about 4517.6415307105. The cubic root of 20409085 is about 273.2799973597.

Adding to 20409085 its reverse (58090402), we get a palindrome (78499487).

The spelling of 20409085 in words is "twenty million, four hundred nine thousand, eighty-five".