115555556665 has 4 divisors (see below), whose sum is σ = 138666668004. Its totient is φ = 92444445328.

The previous prime is 115555556653. The next prime is 115555556681. The reversal of 115555556665 is 566655555511.

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

It can be written as a sum of positive squares in 2 ways, for example, as 68673347136 + 46882209529 = 262056^2 + 216523^2 .

It is a cyclic number.

It is not a de Polignac number, because 115555556665 - 2⁷ = 115555556537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11555555662 + ... + 11555555671.

It is an arithmetic number, because the mean of its divisors is an integer number (34666667001).

Almost surely, 2^115555556665 is an apocalyptic number.

It is an amenable number.

115555556665 is a deficient number, since it is larger than the sum of its proper divisors (23111111339).

115555556665 is an equidigital number, since it uses as much as digits as its factorization.

115555556665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23111111338.

The product of its digits is 16875000, while the sum is 55.

It can be divided in two parts, 115555 and 556665, that added together give a triangular number (672220 = T₁₁₅₉).

The spelling of 115555556665 in words is "one hundred fifteen billion, five hundred fifty-five million, five hundred fifty-six thousand, six hundred sixty-five".