11551721558 has 24 divisors (see below), whose sum is σ = 18783925200. Its totient is φ = 5325619104.

The previous prime is 11551721543. The next prime is 11551721647. The reversal of 11551721558 is 85512715511.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 292028 + ... + 329216.

It is an arithmetic number, because the mean of its divisors is an integer number (782663550).

Almost surely, 2^11551721558 is an apocalyptic number.

11551721558 is a deficient number, since it is larger than the sum of its proper divisors (7232203642).

11551721558 is a wasteful number, since it uses less digits than its factorization.

11551721558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38136 (or 38123 counting only the distinct ones).

The product of its digits is 70000, while the sum is 41.

The spelling of 11551721558 in words is "eleven billion, five hundred fifty-one million, seven hundred twenty-one thousand, five hundred fifty-eight".