1668738739 has 8 divisors (see below), whose sum is σ = 1718938208. Its totient is φ = 1618807680.

The previous prime is 1668738737. The next prime is 1668738749. The reversal of 1668738739 is 9378378661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1668738739 - 2¹ = 1668738737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1668738737) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54447 + ... + 79384.

It is an arithmetic number, because the mean of its divisors is an integer number (214867276).

Almost surely, 2^1668738739 is an apocalyptic number.

1668738739 is a deficient number, since it is larger than the sum of its proper divisors (50199469).

1668738739 is a wasteful number, since it uses less digits than its factorization.

1668738739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134205.

The product of its digits is 9144576, while the sum is 58.

The square root of 1668738739 is about 40850.1987632863. The cubic root of 1668738739 is about 1186.1222406983.

The spelling of 1668738739 in words is "one billion, six hundred sixty-eight million, seven hundred thirty-eight thousand, seven hundred thirty-nine".