1966983509 has 2 divisors, whose sum is σ = 1966983510. Its totient is φ = 1966983508.

The previous prime is 1966983479. The next prime is 1966983517. The reversal of 1966983509 is 9053896691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1966922500 + 61009 = 44350^2 + 247^2 .

It is a cyclic number.

It is not a de Polignac number, because 1966983509 - 2²⁰ = 1965934933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1966983539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 983491754 + 983491755.

It is an arithmetic number, because the mean of its divisors is an integer number (983491755).

Almost surely, 2^1966983509 is an apocalyptic number.

It is an amenable number.

1966983509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1966983509 is an equidigital number, since it uses as much as digits as its factorization.

1966983509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3149280, while the sum is 56.

The square root of 1966983509 is about 44350.6878075188. The cubic root of 1966983509 is about 1252.9495167268.

The spelling of 1966983509 in words is "one billion, nine hundred sixty-six million, nine hundred eighty-three thousand, five hundred nine".