720735578 has 4 divisors (see below), whose sum is σ = 1081103370. Its totient is φ = 360367788.

The previous prime is 720735571. The next prime is 720735649. The reversal of 720735578 is 875537027.

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., 647855209 + 72880369 = 25453^2 + 8537^2 .

It is not an unprimeable number, because it can be changed into a prime (720735571) 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 as a sum of consecutive naturals, namely, 180183893 + ... + 180183896.

Almost surely, 2^720735578 is an apocalyptic number.

720735578 is a deficient number, since it is larger than the sum of its proper divisors (360367792).

720735578 is a wasteful number, since it uses less digits than its factorization.

720735578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360367791.

The product of its (nonzero) digits is 411600, while the sum is 44.

The square root of 720735578 is about 26846.5189177294. The cubic root of 720735578 is about 896.5860697555.

The spelling of 720735578 in words is "seven hundred twenty million, seven hundred thirty-five thousand, five hundred seventy-eight".