66875855 has 4 divisors (see below), whose sum is σ = 80251032. Its totient is φ = 53500680.

The previous prime is 66875843. The next prime is 66875857. The reversal of 66875855 is 55857866.

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

It is not a de Polignac number, because 66875855 - 2¹⁰ = 66874831 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66875857) 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, 6687581 + ... + 6687590.

It is an arithmetic number, because the mean of its divisors is an integer number (20062758).

Almost surely, 2^66875855 is an apocalyptic number.

66875855 is a deficient number, since it is larger than the sum of its proper divisors (13375177).

66875855 is a wasteful number, since it uses less digits than its factorization.

66875855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13375176.

The product of its digits is 2016000, while the sum is 50.

The square root of 66875855 is about 8177.7658929563. The cubic root of 66875855 is about 405.9037987832.

The spelling of 66875855 in words is "sixty-six million, eight hundred seventy-five thousand, eight hundred fifty-five".