20983493 has 2 divisors, whose sum is σ = 20983494. Its totient is φ = 20983492.

The previous prime is 20983463. The next prime is 20983507. The reversal of 20983493 is 39438902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11607649 + 9375844 = 3407^2 + 3062^2 .

It is a cyclic number.

It is not a de Polignac number, because 20983493 - 2¹⁴ = 20967109 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20983453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10491746 + 10491747.

It is an arithmetic number, because the mean of its divisors is an integer number (10491747).

Almost surely, 2^20983493 is an apocalyptic number.

It is an amenable number.

20983493 is a deficient number, since it is larger than the sum of its proper divisors (1).

20983493 is an equidigital number, since it uses as much as digits as its factorization.

20983493 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 20983493 is about 4580.7742795296. The cubic root of 20983493 is about 275.8201104965.

The spelling of 20983493 in words is "twenty million, nine hundred eighty-three thousand, four hundred ninety-three".