720831 has 8 divisors (see below), whose sum is σ = 966064. Its totient is φ = 478080.

The previous prime is 720829. The next prime is 720847. The reversal of 720831 is 138027.

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

It is not a de Polignac number, because 720831 - 2¹ = 720829 is a prime.

It is a super-2 number, since 2×720831² = 1039194661122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 720798 and 720807.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 720831.

It is not an unprimeable number, because it can be changed into a prime (720931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 225 + ... + 1221.

It is an arithmetic number, because the mean of its divisors is an integer number (120758).

2⁷²⁰⁸³¹ is an apocalyptic number.

720831 is a deficient number, since it is larger than the sum of its proper divisors (245233).

720831 is a wasteful number, since it uses less digits than its factorization.

720831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1241.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 720831 is about 849.0176676607. The cubic root of 720831 is about 89.6625635935.

Adding to 720831 its reverse (138027), we get a palindrome (858858).

It can be divided in two parts, 720 and 831, that added together give a palindrome (1551).

The spelling of 720831 in words is "seven hundred twenty thousand, eight hundred thirty-one".