66015877 has 4 divisors (see below), whose sum is σ = 66064140. Its totient is φ = 65967616.

The previous prime is 66015869. The next prime is 66015883. The reversal of 66015877 is 77851066.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77851066 = 2 ⋅38925533.

It can be written as a sum of positive squares in 2 ways, for example, as 8726116 + 57289761 = 2954^2 + 7569^2 .

It is a cyclic number.

It is not a de Polignac number, because 66015877 - 2³ = 66015869 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66015827) 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, 22018 + ... + 24835.

It is an arithmetic number, because the mean of its divisors is an integer number (16516035).

Almost surely, 2^66015877 is an apocalyptic number.

It is an amenable number.

66015877 is a deficient number, since it is larger than the sum of its proper divisors (48263).

66015877 is a wasteful number, since it uses less digits than its factorization.

66015877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48262.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 66015877 is about 8125.0155076775. The cubic root of 66015877 is about 404.1564049024.

The spelling of 66015877 in words is "sixty-six million, fifteen thousand, eight hundred seventy-seven".