1668918079 has 4 divisors (see below), whose sum is σ = 1709623440. Its totient is φ = 1628212720.

The previous prime is 1668918061. The next prime is 1668918091. The reversal of 1668918079 is 9708198661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9708198661 = 7 ⋅1386885523.

It is a cyclic number.

It is not a de Polignac number, because 1668918079 - 2⁹ = 1668917567 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 (1668918179) 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, 20352619 + ... + 20352700.

It is an arithmetic number, because the mean of its divisors is an integer number (427405860).

Almost surely, 2^1668918079 is an apocalyptic number.

1668918079 is a deficient number, since it is larger than the sum of its proper divisors (40705361).

1668918079 is an equidigital number, since it uses as much as digits as its factorization.

1668918079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40705360.

The product of its (nonzero) digits is 1306368, while the sum is 55.

The square root of 1668918079 is about 40852.3937976711. The cubic root of 1668918079 is about 1186.1647301821.

The spelling of 1668918079 in words is "one billion, six hundred sixty-eight million, nine hundred eighteen thousand, seventy-nine".