66106165106615 has 4 divisors (see below), whose sum is σ = 79327398127944. Its totient is φ = 52884932085288.

The previous prime is 66106165106591. The next prime is 66106165106617. The reversal of 66106165106615 is 51660156160166.

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

It is a cyclic number.

It is not a de Polignac number, because 66106165106615 - 2¹⁸ = 66106164844471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66106165106617) 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, 6610616510657 + ... + 6610616510666.

It is an arithmetic number, because the mean of its divisors is an integer number (19831849531986).

Almost surely, 2^{66106165106615} is an apocalyptic number.

66106165106615 is a deficient number, since it is larger than the sum of its proper divisors (13221233021329).

66106165106615 is a wasteful number, since it uses less digits than its factorization.

66106165106615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13221233021328.

The product of its (nonzero) digits is 1166400, while the sum is 50.

The spelling of 66106165106615 in words is "sixty-six trillion, one hundred six billion, one hundred sixty-five million, one hundred six thousand, six hundred fifteen".