20686384 has 40 divisors (see below), whose sum is σ = 42497280. Its totient is φ = 9734208.

The previous prime is 20686373. The next prime is 20686409. The reversal of 20686384 is 48368602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24237 + ... + 25075.

It is an arithmetic number, because the mean of its divisors is an integer number (1062432).

Almost surely, 2^20686384 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 20686384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21248640).

20686384 is an abundant number, since it is smaller than the sum of its proper divisors (21810896).

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

20686384 is a wasteful number, since it uses less digits than its factorization.

20686384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 937 (or 931 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 37.

The square root of 20686384 is about 4548.2286661952. The cubic root of 20686384 is about 274.5121222955.

The spelling of 20686384 in words is "twenty million, six hundred eighty-six thousand, three hundred eighty-four".