20124780 has 48 divisors (see below), whose sum is σ = 60686304. Its totient is φ = 4953600.

The previous prime is 20124773. The next prime is 20124799. The reversal of 20124780 is 8742102.

It is a self number, because there is not a number n which added to its sum of digits gives 20124780.

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 15 ways as a sum of consecutive naturals, for example, 12121 + ... + 13680.

It is an arithmetic number, because the mean of its divisors is an integer number (1264298).

Almost surely, 2^20124780 is an apocalyptic number.

20124780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20124780 is an abundant number, since it is smaller than the sum of its proper divisors (40561524).

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

20124780 is a wasteful number, since it uses less digits than its factorization.

20124780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25826 (or 25824 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 20124780 is about 4486.0650909232. The cubic root of 20124780 is about 272.0051001062.

Adding to 20124780 its reverse (8742102), we get a palindrome (28866882).

The spelling of 20124780 in words is "twenty million, one hundred twenty-four thousand, seven hundred eighty".