66531140220018 has 128 divisors (see below), whose sum is σ = 140020601094144. Its totient is φ = 21057174028800.

The previous prime is 66531140219989. The next prime is 66531140220067. The reversal of 66531140220018 is 81002204113566.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 629899380 + ... + 630004992.

It is an arithmetic number, because the mean of its divisors is an integer number (1093910946048).

Almost surely, 2^{66531140220018} is an apocalyptic number.

66531140220018 is an abundant number, since it is smaller than the sum of its proper divisors (73489460874126).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66531140220018 is a wasteful number, since it uses less digits than its factorization.

66531140220018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106240.

The product of its (nonzero) digits is 69120, while the sum is 39.

The spelling of 66531140220018 in words is "sixty-six trillion, five hundred thirty-one billion, one hundred forty million, two hundred twenty thousand, eighteen".