20783983 has 4 divisors (see below), whose sum is σ = 22673448. Its totient is φ = 18894520.

The previous prime is 20783969. The next prime is 20783993. The reversal of 20783983 is 38938702.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20783983 - 2⁵ = 20783951 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20783953) 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, 944716 + ... + 944737.

It is an arithmetic number, because the mean of its divisors is an integer number (5668362).

Almost surely, 2^20783983 is an apocalyptic number.

20783983 is a deficient number, since it is larger than the sum of its proper divisors (1889465).

20783983 is a wasteful number, since it uses less digits than its factorization.

20783983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1889464.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 20783983 is about 4558.9453824322. The cubic root of 20783983 is about 274.9431640117.

The spelling of 20783983 in words is "twenty million, seven hundred eighty-three thousand, nine hundred eighty-three".