18109186629121 has 27 divisors (see below), whose sum is σ = 21818284328451. Its totient is φ = 14986198150224.

The previous prime is 18109186629113. The next prime is 18109186629137. The reversal of 18109186629121 is 12192668190181.

The square root of 18109186629121 is 4255489.

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., 9496018196721 + 8613168432400 = 3081561^2 + 2934820^2 .

It is not a de Polignac number, because 18109186629121 - 2³ = 18109186629113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18109186629221) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 863853786 + ... + 863874748.

Almost surely, 2^{18109186629121} is an apocalyptic number.

18109186629121 is the 4255489-th square number.

18109186629121 is the 2127745-th centered octagonal number.

It is an amenable number.

18109186629121 is a deficient number, since it is larger than the sum of its proper divisors (3709097699330).

18109186629121 is an frugal number, since it uses more digits than its factorization.

18109186629121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41998 (or 20999 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 55.

The spelling of 18109186629121 in words is "eighteen trillion, one hundred nine billion, one hundred eighty-six million, six hundred twenty-nine thousand, one hundred twenty-one".