18845435723689 has 9 divisors (see below), whose sum is σ = 18925007651109. Its totient is φ = 18766197023040.

The previous prime is 18845435723659. The next prime is 18845435723693. The reversal of 18845435723689 is 98632753454881.

The square root of 18845435723689 is 4341133.

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

It can be written as a sum of positive squares in 4 ways, for example, as 9331344825625 + 9514090898064 = 3054725^2 + 3084492^2 .

It is not a de Polignac number, because 18845435723689 - 2³⁷ = 18707996770217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18845435723659) 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, 1046204047 + ... + 1046222059.

It is an arithmetic number, because the mean of its divisors is an integer number (2102778627901).

Almost surely, 2^{18845435723689} is an apocalyptic number.

18845435723689 is the 4341133-rd square number.

18845435723689 is the 2170567-th centered octagonal number.

It is an amenable number.

18845435723689 is a deficient number, since it is larger than the sum of its proper divisors (79571927420).

18845435723689 is an frugal number, since it uses more digits than its factorization.

18845435723689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36508 (or 18254 counting only the distinct ones).

The product of its digits is 1393459200, while the sum is 73.

The spelling of 18845435723689 in words is "eighteen trillion, eight hundred forty-five billion, four hundred thirty-five million, seven hundred twenty-three thousand, six hundred eighty-nine".