11820690729 has 9 divisors (see below), whose sum is σ = 17074802199. Its totient is φ = 7880243040.

The previous prime is 11820690719. The next prime is 11820690731. The reversal of 11820690729 is 92709602811.

The square root of 11820690729 is 108723.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 78801129 + 11741889600 = 8877^2 + 108360^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 11820690729 - 2⁵ = 11820690697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11820690709) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 308049 + ... + 344289.

Almost surely, 2^11820690729 is an apocalyptic number.

11820690729 is the 108723-rd square number.

11820690729 is the 54362-nd centered octagonal number.

It is an amenable number.

11820690729 is a deficient number, since it is larger than the sum of its proper divisors (5254111470).

11820690729 is an frugal number, since it uses more digits than its factorization.

11820690729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72488 (or 36244 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The spelling of 11820690729 in words is "eleven billion, eight hundred twenty million, six hundred ninety thousand, seven hundred twenty-nine".