66106553 has 4 divisors (see below), whose sum is σ = 66449268. Its totient is φ = 65763840.

The previous prime is 66106519. The next prime is 66106559. The reversal of 66106553 is 35560166.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22915369 + 43191184 = 4787^2 + 6572^2 .

It is a cyclic number.

It is not a de Polignac number, because 66106553 - 2⁸ = 66106297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66106559) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171068 + ... + 171453.

It is an arithmetic number, because the mean of its divisors is an integer number (16612317).

Almost surely, 2^66106553 is an apocalyptic number.

It is an amenable number.

66106553 is a deficient number, since it is larger than the sum of its proper divisors (342715).

66106553 is a wasteful number, since it uses less digits than its factorization.

66106553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342714.

The product of its (nonzero) digits is 16200, while the sum is 32.

The square root of 66106553 is about 8130.5936437630. The cubic root of 66106553 is about 404.3413630351.

The spelling of 66106553 in words is "sixty-six million, one hundred six thousand, five hundred fifty-three".