20723983 has 16 divisors (see below), whose sum is σ = 24466176. Its totient is φ = 17184960.

The previous prime is 20723939. The next prime is 20723999. The reversal of 20723983 is 38932702.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20723983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20723083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46560 + ... + 47002.

It is an arithmetic number, because the mean of its divisors is an integer number (1529136).

Almost surely, 2^20723983 is an apocalyptic number.

20723983 is a deficient number, since it is larger than the sum of its proper divisors (3742193).

20723983 is a wasteful number, since it uses less digits than its factorization.

20723983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 20723983 is about 4552.3601571053. The cubic root of 20723983 is about 274.6783368501.

The spelling of 20723983 in words is "twenty million, seven hundred twenty-three thousand, nine hundred eighty-three".