66515018 has 4 divisors (see below), whose sum is σ = 99772530. Its totient is φ = 33257508.

The previous prime is 66514963. The next prime is 66515021. The reversal of 66515018 is 81051566.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 46471489 + 20043529 = 6817^2 + 4477^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16628753 + ... + 16628756.

Almost surely, 2^66515018 is an apocalyptic number.

66515018 is a deficient number, since it is larger than the sum of its proper divisors (33257512).

66515018 is a wasteful number, since it uses less digits than its factorization.

66515018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33257511.

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 66515018 is about 8155.6739758281. The cubic root of 66515018 is about 405.1724470116.

The spelling of 66515018 in words is "sixty-six million, five hundred fifteen thousand, eighteen".