20183840021 has 8 divisors (see below), whose sum is σ = 20678330904. Its totient is φ = 19689454080.

The previous prime is 20183839969. The next prime is 20183840023. The reversal of 20183840021 is 12004838102.

It can be written as a sum of positive squares in 4 ways, for example, as 2736336100 + 17447503921 = 52310^2 + 132089^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20183840021 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 (20183840023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 482285 + ... + 522461.

It is an arithmetic number, because the mean of its divisors is an integer number (2584791363).

Almost surely, 2^20183840021 is an apocalyptic number.

It is an amenable number.

20183840021 is a deficient number, since it is larger than the sum of its proper divisors (494490883).

20183840021 is a wasteful number, since it uses less digits than its factorization.

20183840021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52471.

The product of its (nonzero) digits is 3072, while the sum is 29.

The spelling of 20183840021 in words is "twenty billion, one hundred eighty-three million, eight hundred forty thousand, twenty-one".