18883639671961 has 9 divisors (see below), whose sum is σ = 18916980777151. Its totient is φ = 18850357250032.

The previous prime is 18883639671943. The next prime is 18883639671973. The reversal of 18883639671961 is 16917693638881.

The square root of 18883639671961 is 4345531.

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., 546882435225 + 18336757236736 = 739515^2 + 4282144^2 .

It is not a de Polignac number, because 18883639671961 - 2⁷ = 18883639671833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18883639671991) 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, 2681189106 + ... + 2681196148.

Almost surely, 2^{18883639671961} is an apocalyptic number.

18883639671961 is the 4345531-st square number.

18883639671961 is the 2172766-th centered octagonal number.

It is an amenable number.

18883639671961 is a deficient number, since it is larger than the sum of its proper divisors (33341105190).

18883639671961 is an frugal number, since it uses more digits than its factorization.

18883639671961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15320 (or 7660 counting only the distinct ones).

The product of its digits is 564350976, while the sum is 76.

The spelling of 18883639671961 in words is "eighteen trillion, eight hundred eighty-three billion, six hundred thirty-nine million, six hundred seventy-one thousand, nine hundred sixty-one".