720417 has 4 divisors (see below), whose sum is σ = 960560. Its totient is φ = 480276.

The previous prime is 720413. The next prime is 720439. The reversal of 720417 is 714027.

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 an emirpimes, since its reverse is a distinct semiprime: 714027 = 3 ⋅238009.

It is not a de Polignac number, because 720417 - 2² = 720413 is a prime.

It is a D-number.

It is a Duffinian number.

720417 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 720393 and 720402.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 720417.

It is not an unprimeable number, because it can be changed into a prime (720413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120067 + ... + 120072.

It is an arithmetic number, because the mean of its divisors is an integer number (240140).

2⁷²⁰⁴¹⁷ is an apocalyptic number.

It is an amenable number.

720417 is a deficient number, since it is larger than the sum of its proper divisors (240143).

720417 is a wasteful number, since it uses less digits than its factorization.

720417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240142.

The product of its (nonzero) digits is 392, while the sum is 21.

The square root of 720417 is about 848.7738214625. The cubic root of 720417 is about 89.6453947934.

The spelling of 720417 in words is "seven hundred twenty thousand, four hundred seventeen", and thus it is an iban number.