1989730073 has 2 divisors, whose sum is σ = 1989730074. Its totient is φ = 1989730072.

The previous prime is 1989730051. The next prime is 1989730087. The reversal of 1989730073 is 3700379891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1927824649 + 61905424 = 43907^2 + 7868^2 .

It is a cyclic number.

It is not a de Polignac number, because 1989730073 - 2¹⁸ = 1989467929 is a prime.

It is not a weakly prime, because it can be changed into another prime (1989730003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 994865036 + 994865037.

It is an arithmetic number, because the mean of its divisors is an integer number (994865037).

Almost surely, 2^1989730073 is an apocalyptic number.

It is an amenable number.

1989730073 is a deficient number, since it is larger than the sum of its proper divisors (1).

1989730073 is an equidigital number, since it uses as much as digits as its factorization.

1989730073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 285768, while the sum is 47.

The square root of 1989730073 is about 44606.3904950849. The cubic root of 1989730073 is about 1257.7607985260.

The spelling of 1989730073 in words is "one billion, nine hundred eighty-nine million, seven hundred thirty thousand, seventy-three".