66189396529 has 3 divisors (see below), whose sum is σ = 66189653803. Its totient is φ = 66189139256.

The previous prime is 66189396509. The next prime is 66189396563. The reversal of 66189396529 is 92569398166.

The square root of 66189396529 is 257273.

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., 4562327025 + 61627069504 = 67545^2 + 248248^2 .

It is not a de Polignac number, because 66189396529 - 2¹³ = 66189388337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66189396509) 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, 128637 + ... + 385909.

Almost surely, 2^66189396529 is an apocalyptic number.

66189396529 is the 257273-rd square number.

66189396529 is the 128637-th centered octagonal number.

It is an amenable number.

66189396529 is a deficient number, since it is larger than the sum of its proper divisors (257274).

66189396529 is an frugal number, since it uses more digits than its factorization.

66189396529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 514546 (or 257273 counting only the distinct ones).

The product of its digits is 37791360, while the sum is 64.

Multiplying 66189396529 by its sum of digits (64), we get a square (4236121377856 = 2058184²).

The spelling of 66189396529 in words is "sixty-six billion, one hundred eighty-nine million, three hundred ninety-six thousand, five hundred twenty-nine".