981491783 has 2 divisors, whose sum is σ = 981491784. Its totient is φ = 981491782.

The previous prime is 981491779. The next prime is 981491839. The reversal of 981491783 is 387194189.

It is a weak prime.

It is an emirp because it is prime and its reverse (387194189) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 981491783 - 2² = 981491779 is a prime.

It is a super-2 number, since 2×981491783² = 1926652240193038178, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (981491723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490745891 + 490745892.

It is an arithmetic number, because the mean of its divisors is an integer number (490745892).

Almost surely, 2^981491783 is an apocalyptic number.

981491783 is a deficient number, since it is larger than the sum of its proper divisors (1).

981491783 is an equidigital number, since it uses as much as digits as its factorization.

981491783 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 50.

The square root of 981491783 is about 31328.7692544728. The cubic root of 981491783 is about 993.7921365095.

The spelling of 981491783 in words is "nine hundred eighty-one million, four hundred ninety-one thousand, seven hundred eighty-three".