720394 has 4 divisors (see below), whose sum is σ = 1080594. Its totient is φ = 360196.

The previous prime is 720373. The next prime is 720397. The reversal of 720394 is 493027.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 664225 + 56169 = 815^2 + 237^2 .

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (720397) 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 as a sum of consecutive naturals, namely, 180097 + ... + 180100.

2⁷²⁰³⁹⁴ is an apocalyptic number.

720394 is a deficient number, since it is larger than the sum of its proper divisors (360200).

720394 is a wasteful number, since it uses less digits than its factorization.

720394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360199.

The product of its (nonzero) digits is 1512, while the sum is 25.

The square root of 720394 is about 848.7602723973. The cubic root of 720394 is about 89.6444407783.

The spelling of 720394 in words is "seven hundred twenty thousand, three hundred ninety-four".