20509260 has 24 divisors (see below), whose sum is σ = 57426096. Its totient is φ = 5469120.

The previous prime is 20509241. The next prime is 20509271. The reversal of 20509260 is 6290502.

It is a self number, because there is not a number n which added to its sum of digits gives 20509260.

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, 170851 + ... + 170970.

It is an arithmetic number, because the mean of its divisors is an integer number (2392754).

Almost surely, 2^20509260 is an apocalyptic number.

20509260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20509260 is an abundant number, since it is smaller than the sum of its proper divisors (36916836).

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

20509260 is a wasteful number, since it uses less digits than its factorization.

20509260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341833 (or 341831 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 20509260 is about 4528.7150495477. The cubic root of 20509260 is about 273.7263860701.

Adding to 20509260 its reverse (6290502), we get a palindrome (26799762).

The spelling of 20509260 in words is "twenty million, five hundred nine thousand, two hundred sixty".