1665055111 has 2 divisors, whose sum is σ = 1665055112. Its totient is φ = 1665055110.

The previous prime is 1665055109. The next prime is 1665055127. The reversal of 1665055111 is 1115505661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1665055111 - 2¹ = 1665055109 is a prime.

Together with 1665055109, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665055211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832527555 + 832527556.

It is an arithmetic number, because the mean of its divisors is an integer number (832527556).

Almost surely, 2^1665055111 is an apocalyptic number.

1665055111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665055111 is an equidigital number, since it uses as much as digits as its factorization.

1665055111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4500, while the sum is 31.

The square root of 1665055111 is about 40805.0868275023. The cubic root of 1665055111 is about 1185.2488361578.

The spelling of 1665055111 in words is "one billion, six hundred sixty-five million, fifty-five thousand, one hundred eleven".