66815095 has 4 divisors (see below), whose sum is σ = 80178120. Its totient is φ = 53452072.

The previous prime is 66815087. The next prime is 66815107. The reversal of 66815095 is 59051866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 59051866 = 2 ⋅29525933.

It is a cyclic number.

It is not a de Polignac number, because 66815095 - 2³ = 66815087 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6681505 + ... + 6681514.

It is an arithmetic number, because the mean of its divisors is an integer number (20044530).

Almost surely, 2^66815095 is an apocalyptic number.

66815095 is a deficient number, since it is larger than the sum of its proper divisors (13363025).

66815095 is a wasteful number, since it uses less digits than its factorization.

66815095 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13363024.

The product of its (nonzero) digits is 64800, while the sum is 40.

The square root of 66815095 is about 8174.0500977178. The cubic root of 66815095 is about 405.7808336878.

The spelling of 66815095 in words is "sixty-six million, eight hundred fifteen thousand, ninety-five".