1985756873 has 2 divisors, whose sum is σ = 1985756874. Its totient is φ = 1985756872.

The previous prime is 1985756849. The next prime is 1985756891. The reversal of 1985756873 is 3786575891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1264726969 + 721029904 = 35563^2 + 26852^2 .

It is a cyclic number.

It is not a de Polignac number, because 1985756873 - 2⁶ = 1985756809 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1985756833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 992878436 + 992878437.

It is an arithmetic number, because the mean of its divisors is an integer number (992878437).

Almost surely, 2^1985756873 is an apocalyptic number.

It is an amenable number.

1985756873 is a deficient number, since it is larger than the sum of its proper divisors (1).

1985756873 is an equidigital number, since it uses as much as digits as its factorization.

1985756873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12700800, while the sum is 59.

The square root of 1985756873 is about 44561.8320202390. The cubic root of 1985756873 is about 1256.9230525283.

The spelling of 1985756873 in words is "one billion, nine hundred eighty-five million, seven hundred fifty-six thousand, eight hundred seventy-three".