720812017 has 4 divisors (see below), whose sum is σ = 720866160. Its totient is φ = 720757876.

The previous prime is 720812009. The next prime is 720812039. The reversal of 720812017 is 710218027.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 710218027 = 17 ⋅41777531.

It is a cyclic number.

It is not a de Polignac number, because 720812017 - 2³ = 720812009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (720812077) 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, 8334 + ... + 38872.

It is an arithmetic number, because the mean of its divisors is an integer number (180216540).

Almost surely, 2^720812017 is an apocalyptic number.

It is an amenable number.

720812017 is a deficient number, since it is larger than the sum of its proper divisors (54143).

720812017 is a wasteful number, since it uses less digits than its factorization.

720812017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54142.

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 720812017 is about 26847.9425096226. The cubic root of 720812017 is about 896.6177650226.

The spelling of 720812017 in words is "seven hundred twenty million, eight hundred twelve thousand, seventeen".