20490505 has 8 divisors (see below), whose sum is σ = 28101312. Its totient is φ = 14050608.

The previous prime is 20490497. The next prime is 20490517. The reversal of 20490505 is 50509402.

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

It is a cyclic number.

It is not a de Polignac number, because 20490505 - 2³ = 20490497 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20490505.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 292687 + ... + 292756.

It is an arithmetic number, because the mean of its divisors is an integer number (3512664).

Almost surely, 2^20490505 is an apocalyptic number.

It is an amenable number.

20490505 is a deficient number, since it is larger than the sum of its proper divisors (7610807).

20490505 is an equidigital number, since it uses as much as digits as its factorization.

20490505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 585455.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 20490505 is about 4526.6439002864. The cubic root of 20490505 is about 273.6429228923.

Adding to 20490505 its reverse (50509402), we get a palindrome (70999907).

It can be divided in two parts, 204 and 90505, that added together give a palindrome (90709).

The spelling of 20490505 in words is "twenty million, four hundred ninety thousand, five hundred five".