716601721 has 4 divisors (see below), whose sum is σ = 781747344. Its totient is φ = 651456100.

The previous prime is 716601713. The next prime is 716601733. The reversal of 716601721 is 127106617.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 716601721 - 2³ = 716601713 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (716601761) 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, 32572795 + ... + 32572816.

It is an arithmetic number, because the mean of its divisors is an integer number (195436836).

Almost surely, 2^716601721 is an apocalyptic number.

It is an amenable number.

716601721 is a deficient number, since it is larger than the sum of its proper divisors (65145623).

716601721 is a wasteful number, since it uses less digits than its factorization.

716601721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65145622.

The product of its (nonzero) digits is 3528, while the sum is 31.

The square root of 716601721 is about 26769.4176440206. The cubic root of 716601721 is about 894.8686265147.

The spelling of 716601721 in words is "seven hundred sixteen million, six hundred one thousand, seven hundred twenty-one".