720860665 has 16 divisors (see below), whose sum is σ = 1040641920. Its totient is φ = 468288000.

The previous prime is 720860599. The next prime is 720860671. The reversal of 720860665 is 566068027.

It is not a de Polignac number, because 720860665 - 2¹⁹ = 720336377 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 541336 + ... + 542665.

It is an arithmetic number, because the mean of its divisors is an integer number (65040120).

Almost surely, 2^720860665 is an apocalyptic number.

It is an amenable number.

720860665 is a deficient number, since it is larger than the sum of its proper divisors (319781255).

720860665 is a wasteful number, since it uses less digits than its factorization.

720860665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1084032.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 720860665 is about 26848.8484855496. The cubic root of 720860665 is about 896.6379356444.

The spelling of 720860665 in words is "seven hundred twenty million, eight hundred sixty thousand, six hundred sixty-five".