66281938042384 has 15 divisors (see below), whose sum is σ = 128421318052783. Its totient is φ = 33140952738448.

The previous prime is 66281938042367. The next prime is 66281938042417. The reversal of 66281938042384 is 48324083918266.

It is a happy number.

The square root of 66281938042384 is 8141372.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 31547817 + ... + 33583159.

Almost surely, 2^{66281938042384} is an apocalyptic number.

66281938042384 is the 8141372-nd square number.

It is an amenable number.

66281938042384 is a deficient number, since it is larger than the sum of its proper divisors (62139380010399).

66281938042384 is an frugal number, since it uses more digits than its factorization.

66281938042384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4070694 (or 2035345 counting only the distinct ones).

The product of its (nonzero) digits is 95551488, while the sum is 64.

The spelling of 66281938042384 in words is "sixty-six trillion, two hundred eighty-one billion, nine hundred thirty-eight million, forty-two thousand, three hundred eighty-four".