20015424 has 224 divisors, whose sum is σ = 69982080. Its totient is φ = 5598720.

The previous prime is 20015419. The next prime is 20015431. The reversal of 20015424 is 42451002.

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 = 20015397 and 20015406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1539642 + ... + 1539654.

It is an arithmetic number, because the mean of its divisors is an integer number (312420).

Almost surely, 2^20015424 is an apocalyptic number.

20015424 is a gapful number since it is divisible by the number (24) 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 20015424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34991040).

20015424 is an abundant number, since it is smaller than the sum of its proper divisors (49966656).

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

20015424 is an equidigital number, since it uses as much as digits as its factorization.

20015424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57 (or 29 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 20015424 is about 4473.8600782769. The cubic root of 20015424 is about 271.5115223583.

Adding to 20015424 its reverse (42451002), we get a palindrome (62466426).

The spelling of 20015424 in words is "twenty million, fifteen thousand, four hundred twenty-four".