20663916 has 96 divisors (see below), whose sum is σ = 60211200. Its totient is φ = 5370624.

The previous prime is 20663861. The next prime is 20663927. The reversal of 20663916 is 61936602.

It is a happy 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, 138610 + ... + 138758.

It is an arithmetic number, because the mean of its divisors is an integer number (627200).

Almost surely, 2^20663916 is an apocalyptic number.

20663916 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 20663916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30105600).

20663916 is an abundant number, since it is smaller than the sum of its proper divisors (39547284).

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

20663916 is a wasteful number, since it uses less digits than its factorization.

20663916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303 (or 301 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 33.

The square root of 20663916 is about 4545.7580225965. The cubic root of 20663916 is about 274.4127014608.

The spelling of 20663916 in words is "twenty million, six hundred sixty-three thousand, nine hundred sixteen".