66915265 has 4 divisors (see below), whose sum is σ = 80298324. Its totient is φ = 53532208.

The previous prime is 66915259. The next prime is 66915269. The reversal of 66915265 is 56251966.

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 14265729 + 52649536 = 3777^2 + 7256^2 .

It is a cyclic number.

It is not a de Polignac number, because 66915265 - 2⁷ = 66915137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66915269) 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, 6691522 + ... + 6691531.

It is an arithmetic number, because the mean of its divisors is an integer number (20074581).

Almost surely, 2^66915265 is an apocalyptic number.

It is an amenable number.

66915265 is a deficient number, since it is larger than the sum of its proper divisors (13383059).

66915265 is a wasteful number, since it uses less digits than its factorization.

66915265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13383058.

The product of its digits is 97200, while the sum is 40.

The square root of 66915265 is about 8180.1751203749. The cubic root of 66915265 is about 405.9835162809.

The spelling of 66915265 in words is "sixty-six million, nine hundred fifteen thousand, two hundred sixty-five".