20984766 has 64 divisors (see below), whose sum is σ = 49455360. Its totient is φ = 5864960.

The previous prime is 20984753. The next prime is 20984771. The reversal of 20984766 is 66748902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 66040 + ... + 66356.

It is an arithmetic number, because the mean of its divisors is an integer number (772740).

Almost surely, 2^20984766 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20984766, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24727680).

20984766 is an abundant number, since it is smaller than the sum of its proper divisors (28470594).

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

20984766 is a wasteful number, since it uses less digits than its factorization.

20984766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409.

The product of its (nonzero) digits is 145152, while the sum is 42.

The square root of 20984766 is about 4580.9132277309. The cubic root of 20984766 is about 275.8256880855.

The spelling of 20984766 in words is "twenty million, nine hundred eighty-four thousand, seven hundred sixty-six".