18098589961 has 9 divisors (see below), whose sum is σ = 18748241031. Its totient is φ = 17470733784.

The previous prime is 18098589959. The next prime is 18098589967. The reversal of 18098589961 is 16998589081.

The square root of 18098589961 is 134531.

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., 9490461561 + 8608128400 = 97419^2 + 92780^2 .

It is not a de Polignac number, because 18098589961 - 2¹ = 18098589959 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18098589893 and 18098589902.

It is not an unprimeable number, because it can be changed into a prime (18098589967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3899080 + ... + 3903718.

Almost surely, 2^18098589961 is an apocalyptic number.

18098589961 is the 134531-st square number.

18098589961 is the 67266-th centered octagonal number.

It is an amenable number.

18098589961 is a deficient number, since it is larger than the sum of its proper divisors (649651070).

18098589961 is an frugal number, since it uses more digits than its factorization.

18098589961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9336 (or 4668 counting only the distinct ones).

The product of its (nonzero) digits is 11197440, while the sum is 64.

Multiplying 18098589961 by its sum of digits (64), we get a square (1158309757504 = 1076248²).

The spelling of 18098589961 in words is "eighteen billion, ninety-eight million, five hundred eighty-nine thousand, nine hundred sixty-one".