720781287 has 4 divisors (see below), whose sum is σ = 961041720. Its totient is φ = 480520856.

The previous prime is 720781253. The next prime is 720781289. The reversal of 720781287 is 782187027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 782187027 = 3 ⋅260729009.

It is a cyclic number.

It is not a de Polignac number, because 720781287 - 2¹¹ = 720779239 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720781289) 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, 120130212 + ... + 120130217.

It is an arithmetic number, because the mean of its divisors is an integer number (240260430).

Almost surely, 2^720781287 is an apocalyptic number.

720781287 is a deficient number, since it is larger than the sum of its proper divisors (240260433).

720781287 is a wasteful number, since it uses less digits than its factorization.

720781287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240260432.

The product of its (nonzero) digits is 87808, while the sum is 42.

The square root of 720781287 is about 26847.3702064094. The cubic root of 720781287 is about 896.6050231635.

The spelling of 720781287 in words is "seven hundred twenty million, seven hundred eighty-one thousand, two hundred eighty-seven".