18218564159041 has 3 divisors (see below), whose sum is σ = 18218568427363. Its totient is φ = 18218559890720.

The previous prime is 18218564159039. The next prime is 18218564159087. The reversal of 18218564159041 is 14095146581281.

The square root of 18218564159041 is 4268321.

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 can be written as a sum of positive squares in only one way, i.e., 18148699096641 + 69865062400 = 4260129^2 + 264320^2 .

It is not a de Polignac number, because 18218564159041 - 2¹ = 18218564159039 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18218564159941) 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, 2134161 + ... + 6402481.

Almost surely, 2^{18218564159041} is an apocalyptic number.

18218564159041 is the 4268321-st square number.

18218564159041 is the 2134161-st centered octagonal number.

It is an amenable number.

18218564159041 is a deficient number, since it is larger than the sum of its proper divisors (4268322).

18218564159041 is an frugal number, since it uses more digits than its factorization.

18218564159041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8536642 (or 4268321 counting only the distinct ones).

The product of its (nonzero) digits is 2764800, while the sum is 55.

The spelling of 18218564159041 in words is "eighteen trillion, two hundred eighteen billion, five hundred sixty-four million, one hundred fifty-nine thousand, forty-one".