665672111 has 16 divisors (see below), whose sum is σ = 760070304. Its totient is φ = 577542144.

The previous prime is 665672107. The next prime is 665672123. The reversal of 665672111 is 111276566.

It is a cyclic number.

It is not a de Polignac number, because 665672111 - 2² = 665672107 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 (665672101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 214376 + ... + 217458.

It is an arithmetic number, because the mean of its divisors is an integer number (47504394).

Almost surely, 2^665672111 is an apocalyptic number.

665672111 is a deficient number, since it is larger than the sum of its proper divisors (94398193).

665672111 is a wasteful number, since it uses less digits than its factorization.

665672111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4090.

The product of its digits is 15120, while the sum is 35.

The square root of 665672111 is about 25800.6222986966. The cubic root of 665672111 is about 873.1458363328.

The spelling of 665672111 in words is "six hundred sixty-five million, six hundred seventy-two thousand, one hundred eleven".