66702665 has 4 divisors (see below), whose sum is σ = 80043204. Its totient is φ = 53362128.

The previous prime is 66702661. The next prime is 66702667. The reversal of 66702665 is 56620766.

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 20720704 + 45981961 = 4552^2 + 6781^2 .

It is a cyclic number.

It is not a de Polignac number, because 66702665 - 2² = 66702661 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66702661) 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, 6670262 + ... + 6670271.

It is an arithmetic number, because the mean of its divisors is an integer number (20010801).

Almost surely, 2^66702665 is an apocalyptic number.

It is an amenable number.

66702665 is a deficient number, since it is larger than the sum of its proper divisors (13340539).

66702665 is a wasteful number, since it uses less digits than its factorization.

66702665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13340538.

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 66702665 is about 8167.1699504786. The cubic root of 66702665 is about 405.5531029508.

The spelling of 66702665 in words is "sixty-six million, seven hundred two thousand, six hundred sixty-five".