66697189281 has 12 divisors (see below), whose sum is σ = 97275729408. Its totient is φ = 44033095224.

The previous prime is 66697189261. The next prime is 66697189319. The reversal of 66697189281 is 18298179666.

It is not a de Polignac number, because 66697189281 - 2¹⁸ = 66696927137 is a prime.

It is a super-3 number, since 3×66697189281³ (a number of 33 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (66697189231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35973825 + ... + 35975678.

It is an arithmetic number, because the mean of its divisors is an integer number (8106310784).

Almost surely, 2^66697189281 is an apocalyptic number.

It is an amenable number.

66697189281 is a deficient number, since it is larger than the sum of its proper divisors (30578540127).

66697189281 is a wasteful number, since it uses less digits than its factorization.

66697189281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71949612 (or 71949609 counting only the distinct ones).

The product of its digits is 15676416, while the sum is 63.

The spelling of 66697189281 in words is "sixty-six billion, six hundred ninety-seven million, one hundred eighty-nine thousand, two hundred eighty-one".