21606102 has 112 divisors (see below), whose sum is σ = 58235040. Its totient is φ = 5878656.

The previous prime is 21606083. The next prime is 21606119. The reversal of 21606102 is 20160612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 295938 + ... + 296010.

Almost surely, 2^21606102 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21606102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29117520).

21606102 is an abundant number, since it is smaller than the sum of its proper divisors (36628938).

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

21606102 is an equidigital number, since it uses as much as digits as its factorization.

21606102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 114 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 21606102 is about 4648.2364397694. The cubic root of 21606102 is about 278.5215525245.

Adding to 21606102 its reverse (20160612), we get a palindrome (41766714).

It can be divided in two parts, 2160610 and 2, that added together give a palindrome (2160612).

The spelling of 21606102 in words is "twenty-one million, six hundred six thousand, one hundred two".