20659983 has 8 divisors (see below), whose sum is σ = 28066608. Its totient is φ = 13513344.

The previous prime is 20659943. The next prime is 20659997. The reversal of 20659983 is 38995602.

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

It is not a de Polignac number, because 20659983 - 2¹⁰ = 20658959 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20659943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64810 + ... + 65127.

It is an arithmetic number, because the mean of its divisors is an integer number (3508326).

Almost surely, 2^20659983 is an apocalyptic number.

20659983 is a deficient number, since it is larger than the sum of its proper divisors (7406625).

20659983 is a wasteful number, since it uses less digits than its factorization.

20659983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129993.

The product of its (nonzero) digits is 116640, while the sum is 42.

The square root of 20659983 is about 4545.3254008927. The cubic root of 20659983 is about 274.3952905365.

The spelling of 20659983 in words is "twenty million, six hundred fifty-nine thousand, nine hundred eighty-three".