1664565111 has 24 divisors (see below), whose sum is σ = 2624244480. Its totient is φ = 1008330000.

The previous prime is 1664565107. The next prime is 1664565121. The reversal of 1664565111 is 1115654661.

1664565111 is a `hidden beast` number, since 1 + 6 + 645 + 6 + 5 + 1 + 1 + 1 = 666.

It is not a de Polignac number, because 1664565111 - 2² = 1664565107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664565121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 347986 + ... + 352736.

It is an arithmetic number, because the mean of its divisors is an integer number (109343520).

Almost surely, 2^1664565111 is an apocalyptic number.

1664565111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1664565111 is a deficient number, since it is larger than the sum of its proper divisors (959679369).

1664565111 is a wasteful number, since it uses less digits than its factorization.

1664565111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8307 (or 8304 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 1664565111 is about 40799.0822323248. The cubic root of 1664565111 is about 1185.1325579425.

The spelling of 1664565111 in words is "one billion, six hundred sixty-four million, five hundred sixty-five thousand, one hundred eleven".