1155665663 has 4 divisors (see below), whose sum is σ = 1167579840. Its totient is φ = 1143751488.

The previous prime is 1155665639. The next prime is 1155665669. The reversal of 1155665663 is 3665665511.

It is a happy number.

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-1155665663 is a prime.

It is a super-3 number, since 3×1155665663³ (a number of 28 digits) contains 333 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 (1155665669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5956943 + ... + 5957136.

It is an arithmetic number, because the mean of its divisors is an integer number (291894960).

Almost surely, 2^1155665663 is an apocalyptic number.

1155665663 is a deficient number, since it is larger than the sum of its proper divisors (11914177).

1155665663 is an equidigital number, since it uses as much as digits as its factorization.

1155665663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11914176.

The product of its digits is 486000, while the sum is 44.

The square root of 1155665663 is about 33995.0829238583. The cubic root of 1155665663 is about 1049.4072733287.

The spelling of 1155665663 in words is "one billion, one hundred fifty-five million, six hundred sixty-five thousand, six hundred sixty-three".