20415224 has 8 divisors (see below), whose sum is σ = 38278560. Its totient is φ = 10207608.

The previous prime is 20415221. The next prime is 20415233. The reversal of 20415224 is 42251402.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 20415196 and 20415205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20415221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1275944 + ... + 1275959.

It is an arithmetic number, because the mean of its divisors is an integer number (4784820).

Almost surely, 2^20415224 is an apocalyptic number.

It is an amenable number.

20415224 is a deficient number, since it is larger than the sum of its proper divisors (17863336).

20415224 is a wasteful number, since it uses less digits than its factorization.

20415224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2551909 (or 2551905 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 20415224 is about 4518.3209270701. The cubic root of 20415224 is about 273.3073952517.

Adding to 20415224 its reverse (42251402), we get a palindrome (62666626).

The spelling of 20415224 in words is "twenty million, four hundred fifteen thousand, two hundred twenty-four".