1966665542111 has 4 divisors (see below), whose sum is σ = 1969009602000. Its totient is φ = 1964321482224.

The previous prime is 1966665542099. The next prime is 1966665542119. The reversal of 1966665542111 is 1112455666691.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1966665542111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1966665542119) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1172028686 + ... + 1172030363.

It is an arithmetic number, because the mean of its divisors is an integer number (492252400500).

Almost surely, 2^{1966665542111} is an apocalyptic number.

1966665542111 is a deficient number, since it is larger than the sum of its proper divisors (2344059889).

1966665542111 is an equidigital number, since it uses as much as digits as its factorization.

1966665542111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2344059888.

The product of its digits is 2332800, while the sum is 53.

The spelling of 1966665542111 in words is "one trillion, nine hundred sixty-six billion, six hundred sixty-five million, five hundred forty-two thousand, one hundred eleven".