1668673397 has 4 divisors (see below), whose sum is σ = 1713772716. Its totient is φ = 1623574080.

The previous prime is 1668673393. The next prime is 1668673399. The reversal of 1668673397 is 7933768661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1407075121 + 261598276 = 37511^2 + 16174^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668673397 - 2² = 1668673393 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668673393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22549604 + ... + 22549677.

It is an arithmetic number, because the mean of its divisors is an integer number (428443179).

Almost surely, 2^1668673397 is an apocalyptic number.

It is an amenable number.

1668673397 is a deficient number, since it is larger than the sum of its proper divisors (45099319).

1668673397 is an equidigital number, since it uses as much as digits as its factorization.

1668673397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45099318.

The product of its digits is 6858432, while the sum is 56.

The square root of 1668673397 is about 40849.3989796668. The cubic root of 1668673397 is about 1186.1067590236.

The spelling of 1668673397 in words is "one billion, six hundred sixty-eight million, six hundred seventy-three thousand, three hundred ninety-seven".