20023605 has 60 divisors (see below), whose sum is σ = 41795820. Its totient is φ = 9144576.

The previous prime is 20023589. The next prime is 20023609. The reversal of 20023605 is 50632002.

It can be written as a sum of positive squares in 2 ways, for example, as 6671889 + 13351716 = 2583^2 + 3654^2 .

It is not a de Polignac number, because 20023605 - 2⁴ = 20023589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20023609) 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 59 ways as a sum of consecutive naturals, for example, 19341 + ... + 20349.

It is an arithmetic number, because the mean of its divisors is an integer number (696597).

Almost surely, 2^20023605 is an apocalyptic number.

It is an amenable number.

20023605 is an abundant number, since it is smaller than the sum of its proper divisors (21772215).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20023605 is a wasteful number, since it uses less digits than its factorization.

20023605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1040 (or 1024 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 20023605 is about 4474.7742959841. The cubic root of 20023605 is about 271.5485093872.

Adding to 20023605 its reverse (50632002), we get a palindrome (70655607).

The spelling of 20023605 in words is "twenty million, twenty-three thousand, six hundred five".