21767016 has 64 divisors (see below), whose sum is σ = 58060800. Its totient is φ = 6784448.

The previous prime is 21766981. The next prime is 21767029. The reversal of 21767016 is 61076712.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25525 + ... + 26363.

It is an arithmetic number, because the mean of its divisors is an integer number (907200).

Almost surely, 2^21767016 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 21767016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29030400).

21767016 is an abundant number, since it is smaller than the sum of its proper divisors (36293784).

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

21767016 is a wasteful number, since it uses less digits than its factorization.

21767016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 918 (or 914 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 30.

The square root of 21767016 is about 4665.5134765640. The cubic root of 21767016 is about 279.2112837972.

The spelling of 21767016 in words is "twenty-one million, seven hundred sixty-seven thousand, sixteen".