717640427 has 12 divisors (see below), whose sum is σ = 836910936. Its totient is φ = 613569600.

The previous prime is 717640403. The next prime is 717640433. The reversal of 717640427 is 724046717.

It is not a de Polignac number, because 717640427 - 2²⁴ = 700863211 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (717640477) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1388 + ... + 37910.

It is an arithmetic number, because the mean of its divisors is an integer number (69742578).

Almost surely, 2^717640427 is an apocalyptic number.

717640427 is a deficient number, since it is larger than the sum of its proper divisors (119270509).

717640427 is a wasteful number, since it uses less digits than its factorization.

717640427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36938 (or 36931 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 38.

The square root of 717640427 is about 26788.8116011144. The cubic root of 717640427 is about 895.3007850593.

The spelling of 717640427 in words is "seven hundred seventeen million, six hundred forty thousand, four hundred twenty-seven".