21116576 has 48 divisors (see below), whose sum is σ = 46738944. Its totient is φ = 9318144.

The previous prime is 21116561. The next prime is 21116587. The reversal of 21116576 is 67561112.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8465 + ... + 10671.

It is an arithmetic number, because the mean of its divisors is an integer number (973728).

Almost surely, 2^21116576 is an apocalyptic number.

21116576 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21116576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23369472).

21116576 is an abundant number, since it is smaller than the sum of its proper divisors (25622368).

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

21116576 is a wasteful number, since it uses less digits than its factorization.

21116576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2253 (or 2245 counting only the distinct ones).

The product of its digits is 2520, while the sum is 29.

The square root of 21116576 is about 4595.2775759469. The cubic root of 21116576 is about 276.4019907106.

Adding to 21116576 its reverse (67561112), we get a palindrome (88677688).

The spelling of 21116576 in words is "twenty-one million, one hundred sixteen thousand, five hundred seventy-six".