66166515 has 24 divisors (see below), whose sum is σ = 119676960. Its totient is φ = 33753984.

The previous prime is 66166501. The next prime is 66166523. The reversal of 66166515 is 51566166.

It is not a de Polignac number, because 66166515 - 2⁵ = 66166483 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66166515.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30930 + ... + 32999.

It is an arithmetic number, because the mean of its divisors is an integer number (4986540).

Almost surely, 2^66166515 is an apocalyptic number.

66166515 is a deficient number, since it is larger than the sum of its proper divisors (53510445).

66166515 is a wasteful number, since it uses less digits than its factorization.

66166515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63963 (or 63960 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 66166515 is about 8134.2802385952. The cubic root of 66166515 is about 404.4635788059.

It can be divided in two parts, 6616 and 6515, that added together give a palindrome (13131).

The spelling of 66166515 in words is "sixty-six million, one hundred sixty-six thousand, five hundred fifteen".