18463646161 has 9 divisors (see below), whose sum is σ = 19616085201. Its totient is φ = 17375375232.

The previous prime is 18463646143. The next prime is 18463646197. The reversal of 18463646161 is 16164636481.

The square root of 18463646161 is 135881.

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 646735761 + 17816910400 = 25431^2 + 133480^2 .

It is not a de Polignac number, because 18463646161 - 2¹⁷ = 18463515089 is a prime.

It is a super-2 number, since 2×18463646161² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18463640161) 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, 2305981 + ... + 2313973.

Almost surely, 2^18463646161 is an apocalyptic number.

18463646161 is the 135881-st square number.

18463646161 is the 67941-st centered octagonal number.

It is an amenable number.

18463646161 is a deficient number, since it is larger than the sum of its proper divisors (1152439040).

18463646161 is an frugal number, since it uses more digits than its factorization.

18463646161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16020 (or 8010 counting only the distinct ones).

The product of its digits is 497664, while the sum is 46.

The spelling of 18463646161 in words is "eighteen billion, four hundred sixty-three million, six hundred forty-six thousand, one hundred sixty-one".