20124720 has 320 divisors, whose sum is σ = 87137280. Its totient is φ = 4181760.

The previous prime is 20124661. The next prime is 20124733. The reversal of 20124720 is 2742102.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20124693 and 20124702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1829515 + ... + 1829525.

It is an arithmetic number, because the mean of its divisors is an integer number (272304).

Almost surely, 2^20124720 is an apocalyptic number.

20124720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20124720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43568640).

20124720 is an abundant number, since it is smaller than the sum of its proper divisors (67012560).

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

20124720 is a wasteful number, since it uses less digits than its factorization.

20124720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 20124720 is about 4486.0584035431. The cubic root of 20124720 is about 272.0048297874.

Adding to 20124720 its reverse (2742102), we get a palindrome (22866822).

The spelling of 20124720 in words is "twenty million, one hundred twenty-four thousand, seven hundred twenty".