66161615506 has 16 divisors (see below), whose sum is σ = 113500442880. Its totient is φ = 28334845440.

The previous prime is 66161615489. The next prime is 66161615521. The reversal of 66161615506 is 60551616166.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1657290 + ... + 1696741.

It is an arithmetic number, because the mean of its divisors is an integer number (7093777680).

Almost surely, 2^66161615506 is an apocalyptic number.

66161615506 is a deficient number, since it is larger than the sum of its proper divisors (47338827374).

66161615506 is a wasteful number, since it uses less digits than its factorization.

66161615506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3355449.

The product of its (nonzero) digits is 194400, while the sum is 43.

The spelling of 66161615506 in words is "sixty-six billion, one hundred sixty-one million, six hundred fifteen thousand, five hundred six".