20686976 has 32 divisors (see below), whose sum is σ = 42641100. Its totient is φ = 9985024.

The previous prime is 20686969. The next prime is 20687027. The reversal of 20686976 is 67968602.

It can be written as a sum of positive squares in 2 ways, for example, as 19149376 + 1537600 = 4376^2 + 1240^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 926 + ... + 6498.

Almost surely, 2^20686976 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 20686976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21320550).

20686976 is an abundant number, since it is smaller than the sum of its proper divisors (21954124).

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

20686976 is an equidigital number, since it uses as much as digits as its factorization.

20686976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5616 (or 5604 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 44.

The square root of 20686976 is about 4548.2937460107. The cubic root of 20686976 is about 274.5147409201.

The spelling of 20686976 in words is "twenty million, six hundred eighty-six thousand, nine hundred seventy-six".