1066660116221 has 8 divisors (see below), whose sum is σ = 1220072352384. Its totient is φ = 913505934960.

The previous prime is 1066660116217. The next prime is 1066660116227. The reversal of 1066660116221 is 1226110666601.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1066660116221 - 2² = 1066660116217 is a prime.

It is a super-2 number, since 2×1066660116221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1066660116227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64504865 + ... + 64521398.

It is an arithmetic number, because the mean of its divisors is an integer number (152509044048).

Almost surely, 2^{1066660116221} is an apocalyptic number.

It is an amenable number.

1066660116221 is a deficient number, since it is larger than the sum of its proper divisors (153412236163).

1066660116221 is a wasteful number, since it uses less digits than its factorization.

1066660116221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129027451.

The product of its (nonzero) digits is 31104, while the sum is 38.

The spelling of 1066660116221 in words is "one trillion, sixty-six billion, six hundred sixty million, one hundred sixteen thousand, two hundred twenty-one".