720991069 has 4 divisors (see below), whose sum is σ = 745852860. Its totient is φ = 696129280.

The previous prime is 720991067. The next prime is 720991079. The reversal of 720991069 is 960199027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 960199027 = 181 ⋅5304967.

It can be written as a sum of positive squares in 2 ways, for example, as 426422500 + 294568569 = 20650^2 + 17163^2 .

It is a cyclic number.

It is not a de Polignac number, because 720991069 - 2¹ = 720991067 is a prime.

It is a super-2 number, since 2×720991069² = 1039656243155525522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720991067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12430852 + ... + 12430909.

It is an arithmetic number, because the mean of its divisors is an integer number (186463215).

Almost surely, 2^720991069 is an apocalyptic number.

It is an amenable number.

720991069 is a deficient number, since it is larger than the sum of its proper divisors (24861791).

720991069 is a wasteful number, since it uses less digits than its factorization.

720991069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24861790.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 720991069 is about 26851.2768597696. The cubic root of 720991069 is about 896.6919997787.

The spelling of 720991069 in words is "seven hundred twenty million, nine hundred ninety-one thousand, sixty-nine".