20650880 has 64 divisors (see below), whose sum is σ = 50636880. Its totient is φ = 8048640.

The previous prime is 20650841. The next prime is 20650909. The reversal of 20650880 is 8805602.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25847 + ... + 26633.

Almost surely, 2^20650880 is an apocalyptic number.

20650880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

20650880 is the 2624-th octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20650880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25318440).

20650880 is an abundant number, since it is smaller than the sum of its proper divisors (29986000).

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

20650880 is an equidigital number, since it uses as much as digits as its factorization.

20650880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 847 (or 835 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 20650880 is about 4544.3239321158. The cubic root of 20650880 is about 274.3549841581.

The spelling of 20650880 in words is "twenty million, six hundred fifty thousand, eight hundred eighty".