66145161506 has 4 divisors (see below), whose sum is σ = 99217742262. Its totient is φ = 33072580752.

The previous prime is 66145161493. The next prime is 66145161517. The reversal of 66145161506 is 60516154166.

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., 61357767025 + 4787394481 = 247705^2 + 69191^2 .

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 as a sum of consecutive naturals, namely, 16536290375 + ... + 16536290378.

Almost surely, 2^66145161506 is an apocalyptic number.

66145161506 is a deficient number, since it is larger than the sum of its proper divisors (33072580756).

66145161506 is a wasteful number, since it uses less digits than its factorization.

66145161506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33072580755.

The product of its (nonzero) digits is 129600, while the sum is 41.

The spelling of 66145161506 in words is "sixty-six billion, one hundred forty-five million, one hundred sixty-one thousand, five hundred six".