663491749 has 2 divisors, whose sum is σ = 663491750. Its totient is φ = 663491748.

The previous prime is 663491711. The next prime is 663491753. The reversal of 663491749 is 947194366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 374151649 + 289340100 = 19343^2 + 17010^2 .

It is a cyclic number.

It is not a de Polignac number, because 663491749 - 2²⁷ = 529274021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663494749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331745874 + 331745875.

It is an arithmetic number, because the mean of its divisors is an integer number (331745875).

Almost surely, 2^663491749 is an apocalyptic number.

It is an amenable number.

663491749 is a deficient number, since it is larger than the sum of its proper divisors (1).

663491749 is an equidigital number, since it uses as much as digits as its factorization.

663491749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 49.

The square root of 663491749 is about 25758.3335835221. Note that the first 3 decimals coincide. The cubic root of 663491749 is about 872.1914844228.

The spelling of 663491749 in words is "six hundred sixty-three million, four hundred ninety-one thousand, seven hundred forty-nine".