721769169 has 16 divisors (see below), whose sum is σ = 1105102080. Its totient is φ = 414412560.

The previous prime is 721769149. The next prime is 721769171. The reversal of 721769169 is 961967127.

It is a happy number.

It is not a de Polignac number, because 721769169 - 2¹¹ = 721767121 is a prime.

It is a super-2 number, since 2×721769169² = 1041901466637901122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (721769149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 574947 + ... + 576200.

It is an arithmetic number, because the mean of its divisors is an integer number (69068880).

Almost surely, 2^721769169 is an apocalyptic number.

It is an amenable number.

721769169 is a deficient number, since it is larger than the sum of its proper divisors (383332911).

721769169 is a wasteful number, since it uses less digits than its factorization.

721769169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1151180.

The product of its digits is 285768, while the sum is 48.

The square root of 721769169 is about 26865.7620215768. The cubic root of 721769169 is about 897.0144564783.

The spelling of 721769169 in words is "seven hundred twenty-one million, seven hundred sixty-nine thousand, one hundred sixty-nine".