1818773207161 has 3 divisors (see below), whose sum is σ = 1818774555781. Its totient is φ = 1818771858542.

The previous prime is 1818773207159. The next prime is 1818773207177. The reversal of 1818773207161 is 1617023778181.

The square root of 1818773207161 is 1348619.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1818773207161 - 2¹ = 1818773207159 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1818773207099 and 1818773207108.

It is not an unprimeable number, because it can be changed into a prime (1818773207101) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 674310 + ... + 2022928.

Almost surely, 2^{1818773207161} is an apocalyptic number.

1818773207161 is the 1348619-th square number.

1818773207161 is the 674310-th centered octagonal number.

It is an amenable number.

1818773207161 is a deficient number, since it is larger than the sum of its proper divisors (1348620).

1818773207161 is an frugal number, since it uses more digits than its factorization.

1818773207161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2697238 (or 1348619 counting only the distinct ones).

The product of its (nonzero) digits is 790272, while the sum is 52.

The spelling of 1818773207161 in words is "one trillion, eight hundred eighteen billion, seven hundred seventy-three million, two hundred seven thousand, one hundred sixty-one".