20518444 has 12 divisors (see below), whose sum is σ = 35985600. Its totient is φ = 10236848.

The previous prime is 20518441. The next prime is 20518447. The reversal of 20518444 is 44481502.

It is an interprime number because it is at equal distance from previous prime (20518441) and next prime (20518447).

It is a super-2 number, since 2×20518444² = 842013088362272, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20518441) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3439 + ... + 7270.

It is an arithmetic number, because the mean of its divisors is an integer number (2998800).

Almost surely, 2^20518444 is an apocalyptic number.

It is an amenable number.

20518444 is a deficient number, since it is larger than the sum of its proper divisors (15467156).

20518444 is a wasteful number, since it uses less digits than its factorization.

20518444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11192 (or 11190 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 28.

The square root of 20518444 is about 4529.7289102109. The cubic root of 20518444 is about 273.7672379907.

Adding to 20518444 its reverse (44481502), we get a palindrome (64999946).

The spelling of 20518444 in words is "twenty million, five hundred eighteen thousand, four hundred forty-four".