21973116 has 72 divisors (see below), whose sum is σ = 58019920. Its totient is φ = 6462720.

The previous prime is 21973103. The next prime is 21973157. The reversal of 21973116 is 61137912.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a zygodrome in base 11.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53520 + ... + 53928.

Almost surely, 2^21973116 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 21973116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29009960).

21973116 is an abundant number, since it is smaller than the sum of its proper divisors (36046804).

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

21973116 is a wasteful number, since it uses less digits than its factorization.

21973116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475 (or 462 counting only the distinct ones).

The product of its digits is 2268, while the sum is 30.

The square root of 21973116 is about 4687.5490397435. The cubic root of 21973116 is about 280.0897501403.

The spelling of 21973116 in words is "twenty-one million, nine hundred seventy-three thousand, one hundred sixteen".