20668608 has 98 divisors (see below), whose sum is σ = 61632084. Its totient is φ = 6873984.

The previous prime is 20668589. The next prime is 20668631. The reversal of 20668608 is 80686602.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 46435 + ... + 46877.

Almost surely, 2^20668608 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 20668608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30816042).

20668608 is an abundant number, since it is smaller than the sum of its proper divisors (40963476).

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

20668608 is an frugal number, since it uses more digits than its factorization.

20668608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 20668608 is about 4546.2740788474. The cubic root of 20668608 is about 274.4334694985.

The spelling of 20668608 in words is "twenty million, six hundred sixty-eight thousand, six hundred eight".