717721345 has 8 divisors (see below), whose sum is σ = 939562560. Its totient is φ = 521979120.

The previous prime is 717721343. The next prime is 717721363. The reversal of 717721345 is 543127717.

It is a happy number.

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

It is not a de Polignac number, because 717721345 - 2¹ = 717721343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (717721343) 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, 6524685 + ... + 6524794.

It is an arithmetic number, because the mean of its divisors is an integer number (117445320).

Almost surely, 2^717721345 is an apocalyptic number.

It is an amenable number.

717721345 is a deficient number, since it is larger than the sum of its proper divisors (221841215).

717721345 is a wasteful number, since it uses less digits than its factorization.

717721345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13049495.

The product of its digits is 41160, while the sum is 37.

The square root of 717721345 is about 26790.3218532365. The cubic root of 717721345 is about 895.3344338633.

The spelling of 717721345 in words is "seven hundred seventeen million, seven hundred twenty-one thousand, three hundred forty-five".