18666937129 has 9 divisors (see below), whose sum is σ = 18769557751. Its totient is φ = 18564876760.

The previous prime is 18666937117. The next prime is 18666937141. The reversal of 18666937129 is 92173966681.

The square root of 18666937129 is 136627.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (18666937117) and next prime (18666937141).

It can be written as a sum of positive squares in only one way, i.e., 1044905625 + 17622031504 = 32325^2 + 132748^2 .

It is not a de Polignac number, because 18666937129 - 2¹¹ = 18666935081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18666937169) 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, 43310544 + ... + 43310974.

Almost surely, 2^18666937129 is an apocalyptic number.

18666937129 is the 136627-th square number.

18666937129 is the 68314-th centered octagonal number.

It is an amenable number.

18666937129 is a deficient number, since it is larger than the sum of its proper divisors (102620622).

18666937129 is an frugal number, since it uses more digits than its factorization.

18666937129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1496 (or 748 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 58.

The spelling of 18666937129 in words is "eighteen billion, six hundred sixty-six million, nine hundred thirty-seven thousand, one hundred twenty-nine".