20719983 has 4 divisors (see below), whose sum is σ = 27626648. Its totient is φ = 13813320.

The previous prime is 20719981. The next prime is 20720027. The reversal of 20719983 is 38991702.

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

It is not a de Polignac number, because 20719983 - 2¹ = 20719981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20719981) 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, 3453328 + ... + 3453333.

It is an arithmetic number, because the mean of its divisors is an integer number (6906662).

Almost surely, 2^20719983 is an apocalyptic number.

20719983 is a deficient number, since it is larger than the sum of its proper divisors (6906665).

20719983 is an equidigital number, since it uses as much as digits as its factorization.

20719983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6906664.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 20719983 is about 4551.9208033532. The cubic root of 20719983 is about 274.6606635414.

The spelling of 20719983 in words is "twenty million, seven hundred nineteen thousand, nine hundred eighty-three".