20806680 has 64 divisors (see below), whose sum is σ = 63957600. Its totient is φ = 5411840.

The previous prime is 20806663. The next prime is 20806693. The reversal of 20806680 is 8660802.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2806 + ... + 7034.

Almost surely, 2^20806680 is an apocalyptic number.

20806680 is a gapful number since it is divisible by the number (20) 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 20806680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31978800).

20806680 is an abundant number, since it is smaller than the sum of its proper divisors (43150920).

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

20806680 is a wasteful number, since it uses less digits than its factorization.

20806680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4284 (or 4280 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 20806680 is about 4561.4339850534. The cubic root of 20806680 is about 275.0432108408.

The spelling of 20806680 in words is "twenty million, eight hundred six thousand, six hundred eighty".