20609090 has 8 divisors (see below), whose sum is σ = 37096380. Its totient is φ = 8243632.

The previous prime is 20609089. The next prime is 20609093. The reversal of 20609090 is 9090602.

It can be written as a sum of positive squares in 2 ways, for example, as 19123129 + 1485961 = 4373^2 + 1219^2 .

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

20609090 is a modest number, since divided by 9090 gives 2060 as remainder.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20609093) 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 3 ways as a sum of consecutive naturals, for example, 1030445 + ... + 1030464.

Almost surely, 2^20609090 is an apocalyptic number.

20609090 is a deficient number, since it is larger than the sum of its proper divisors (16487290).

20609090 is a wasteful number, since it uses less digits than its factorization.

20609090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2060916.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 20609090 is about 4539.7235598657. The cubic root of 20609090 is about 274.1697937065.

Adding to 20609090 its reverse (9090602), we get a palindrome (29699692).

The spelling of 20609090 in words is "twenty million, six hundred nine thousand, ninety".