1667489491 has 2 divisors, whose sum is σ = 1667489492. Its totient is φ = 1667489490.

The previous prime is 1667489477. The next prime is 1667489503. The reversal of 1667489491 is 1949847661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1667489491 - 2¹⁹ = 1666965203 is a prime.

It is not a weakly prime, because it can be changed into another prime (1667480491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833744745 + 833744746.

It is an arithmetic number, because the mean of its divisors is an integer number (833744746).

Almost surely, 2^1667489491 is an apocalyptic number.

1667489491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1667489491 is an equidigital number, since it uses as much as digits as its factorization.

1667489491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2612736, while the sum is 55.

The square root of 1667489491 is about 40834.9053017146. The cubic root of 1667489491 is about 1185.8261826208.

The spelling of 1667489491 in words is "one billion, six hundred sixty-seven million, four hundred eighty-nine thousand, four hundred ninety-one".