21618104 has 16 divisors (see below), whose sum is σ = 40639200. Its totient is φ = 10780992.

The previous prime is 21618059. The next prime is 21618109. The reversal of 21618104 is 40181612.

It is a self number, because there is not a number n which added to its sum of digits gives 21618104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21618109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32 + ... + 6575.

It is an arithmetic number, because the mean of its divisors is an integer number (2539950).

Almost surely, 2^21618104 is an apocalyptic number.

It is an amenable number.

21618104 is a deficient number, since it is larger than the sum of its proper divisors (19021096).

21618104 is a wasteful number, since it uses less digits than its factorization.

21618104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7022 (or 7018 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 21618104 is about 4649.5272878003. The cubic root of 21618104 is about 278.5731150707.

Adding to 21618104 its reverse (40181612), we get a palindrome (61799716).

The spelling of 21618104 in words is "twenty-one million, six hundred eighteen thousand, one hundred four".