21841716 has 48 divisors (see below), whose sum is σ = 57780800. Its totient is φ = 6365952.

The previous prime is 21841711. The next prime is 21841723. The reversal of 21841716 is 61714812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21841711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 721 + ... + 6648.

Almost surely, 2^21841716 is an apocalyptic number.

21841716 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 21841716, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28890400).

21841716 is an abundant number, since it is smaller than the sum of its proper divisors (35939084).

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

21841716 is a wasteful number, since it uses less digits than its factorization.

21841716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7408 (or 7406 counting only the distinct ones).

The product of its digits is 2688, while the sum is 30.

The square root of 21841716 is about 4673.5121696643. The cubic root of 21841716 is about 279.5303180214.

The spelling of 21841716 in words is "twenty-one million, eight hundred forty-one thousand, seven hundred sixteen".