20418336 has 72 divisors (see below), whose sum is σ = 59963904. Its totient is φ = 6583680.

The previous prime is 20418311. The next prime is 20418337. The reversal of 20418336 is 63381402.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

It is not an unprimeable number, because it can be changed into a prime (20418337) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7785 + ... + 10071.

It is an arithmetic number, because the mean of its divisors is an integer number (832832).

Almost surely, 2^20418336 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20418336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29981952).

20418336 is an abundant number, since it is smaller than the sum of its proper divisors (39545568).

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

20418336 is a wasteful number, since it uses less digits than its factorization.

20418336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2334 (or 2323 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 20418336 is about 4518.6652896624. The cubic root of 20418336 is about 273.3212817741.

Adding to 20418336 its reverse (63381402), we get a palindrome (83799738).

The spelling of 20418336 in words is "twenty million, four hundred eighteen thousand, three hundred thirty-six".