21106316 has 96 divisors (see below), whose sum is σ = 50803200. Its totient is φ = 7418880.

The previous prime is 21106313. The next prime is 21106331. The reversal of 21106316 is 61360112.

It is not an unprimeable number, because it can be changed into a prime (21106313) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 151775 + ... + 151913.

It is an arithmetic number, because the mean of its divisors is an integer number (529200).

Almost surely, 2^21106316 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 21106316, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25401600).

21106316 is an abundant number, since it is smaller than the sum of its proper divisors (29696884).

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

21106316 is a wasteful number, since it uses less digits than its factorization.

21106316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207 (or 205 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21106316 is about 4594.1610768453. The cubic root of 21106316 is about 276.3572179242.

Adding to 21106316 its reverse (61360112), we get a palindrome (82466428).

The spelling of 21106316 in words is "twenty-one million, one hundred six thousand, three hundred sixteen".