20505360 has 40 divisors (see below), whose sum is σ = 63567360. Its totient is φ = 5468032.

The previous prime is 20505341. The next prime is 20505361. The reversal of 20505360 is 6350502.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42480 + ... + 42959.

It is an arithmetic number, because the mean of its divisors is an integer number (1589184).

Almost surely, 2^20505360 is an apocalyptic number.

20505360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20505360 is an abundant number, since it is smaller than the sum of its proper divisors (43062000).

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

20505360 is a wasteful number, since it uses less digits than its factorization.

20505360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85455 (or 85449 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 21.

The square root of 20505360 is about 4528.2844433626. The cubic root of 20505360 is about 273.7090345489.

Adding to 20505360 its reverse (6350502), we get a palindrome (26855862).

The spelling of 20505360 in words is "twenty million, five hundred five thousand, three hundred sixty".