20966 has 8 divisors (see below), whose sum is σ = 34344. Its totient is φ = 9520.

The previous prime is 20963. The next prime is 20981. The reversal of 20966 is 66902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20963) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 455 + ... + 498.

It is an arithmetic number, because the mean of its divisors is an integer number (4293).

2²⁰⁹⁶⁶ is an apocalyptic number.

20966 is a deficient number, since it is larger than the sum of its proper divisors (13378).

20966 is a wasteful number, since it uses less digits than its factorization.

20966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 966.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 20966 is about 144.7964087952. The cubic root of 20966 is about 27.5743442889.

The spelling of 20966 in words is "twenty thousand, nine hundred sixty-six".