668416769 has 2 divisors, whose sum is σ = 668416770. Its totient is φ = 668416768.

The previous prime is 668416759. The next prime is 668416783. The reversal of 668416769 is 967614866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 430023169 + 238393600 = 20737^2 + 15440^2 .

It is a cyclic number.

It is not a de Polignac number, because 668416769 - 2²⁴ = 651639553 is a prime.

It is a super-2 number, since 2×668416769² = 893561954160798722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 668416769.

It is not a weakly prime, because it can be changed into another prime (668416739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334208384 + 334208385.

It is an arithmetic number, because the mean of its divisors is an integer number (334208385).

Almost surely, 2^668416769 is an apocalyptic number.

It is an amenable number.

668416769 is a deficient number, since it is larger than the sum of its proper divisors (1).

668416769 is an equidigital number, since it uses as much as digits as its factorization.

668416769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2612736, while the sum is 53.

The square root of 668416769 is about 25853.7573478208. The cubic root of 668416769 is about 874.3442244017.

The spelling of 668416769 in words is "six hundred sixty-eight million, four hundred sixteen thousand, seven hundred sixty-nine".