720206618 has 4 divisors (see below), whose sum is σ = 1080309930. Its totient is φ = 360103308.

The previous prime is 720206611. The next prime is 720206633. The reversal of 720206618 is 816602027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 816602027 = 71 ⋅11501437.

It can be written as a sum of positive squares in only one way, i.e., 635695369 + 84511249 = 25213^2 + 9193^2 .

It is a super-3 number, since 3×720206618³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (720206611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180051653 + ... + 180051656.

Almost surely, 2^720206618 is an apocalyptic number.

720206618 is a deficient number, since it is larger than the sum of its proper divisors (360103312).

720206618 is a wasteful number, since it uses less digits than its factorization.

720206618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360103311.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 720206618 is about 26836.6655529334. The cubic root of 720206618 is about 896.3666761937.

The spelling of 720206618 in words is "seven hundred twenty million, two hundred six thousand, six hundred eighteen".