20090505 has 32 divisors (see below), whose sum is σ = 34128000. Its totient is φ = 10063872.

The previous prime is 20090491. The next prime is 20090527. The reversal of 20090505 is 50509002.

It is not a de Polignac number, because 20090505 - 2⁷ = 20090377 is a prime.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 44521 + ... + 44969.

It is an arithmetic number, because the mean of its divisors is an integer number (1066500).

Almost surely, 2^20090505 is an apocalyptic number.

It is an amenable number.

20090505 is a deficient number, since it is larger than the sum of its proper divisors (14037495).

20090505 is a wasteful number, since it uses less digits than its factorization.

20090505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633.

The product of its (nonzero) digits is 450, while the sum is 21.

The square root of 20090505 is about 4482.2432999559. The cubic root of 20090505 is about 271.8505928677.

Adding to 20090505 its reverse (50509002), we get a palindrome (70599507).

The spelling of 20090505 in words is "twenty million, ninety thousand, five hundred five".