717979 has 2 divisors, whose sum is σ = 717980. Its totient is φ = 717978.

The previous prime is 717967. The next prime is 717989. The reversal of 717979 is 979717.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (979717) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 717979 - 2⁷ = 717851 is a prime.

It is not a weakly prime, because it can be changed into another prime (717919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 358989 + 358990.

It is an arithmetic number, because the mean of its divisors is an integer number (358990).

2⁷¹⁷⁹⁷⁹ is an apocalyptic number.

717979 is a deficient number, since it is larger than the sum of its proper divisors (1).

717979 is an equidigital number, since it uses as much as digits as its factorization.

717979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27783, while the sum is 40.

The square root of 717979 is about 847.3364148908. The cubic root of 717979 is about 89.5441559837.

The spelling of 717979 in words is "seven hundred seventeen thousand, nine hundred seventy-nine".