20650 has 24 divisors (see below), whose sum is σ = 44640. Its totient is φ = 6960.

The previous prime is 20641. The next prime is 20663. The reversal of 20650 is 5602.

It is a nialpdrome in base 14.

It is a zygodrome in base 4.

It is a self number, because there is not a number n which added to its sum of digits gives 20650.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 321 + ... + 379.

It is an arithmetic number, because the mean of its divisors is an integer number (1860).

2²⁰⁶⁵⁰ is an apocalyptic number.

20650 is an abundant number, since it is smaller than the sum of its proper divisors (23990).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22320).

20650 is a wasteful number, since it uses less digits than its factorization.

20650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 73 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 20650 is about 143.7010786320. The cubic root of 20650 is about 27.4351087055.

It can be divided in two parts, 206 and 50, that added together give a 8-th power (256 = 2⁸).

The spelling of 20650 in words is "twenty thousand, six hundred fifty".