1155912981 has 8 divisors (see below), whose sum is σ = 1547358624. Its totient is φ = 767538000.

The previous prime is 1155912949. The next prime is 1155912997. The reversal of 1155912981 is 1892195511.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1155912981 - 2⁵ = 1155912949 is a prime.

It is a super-3 number, since 3×1155912981³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1155912931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 766786 + ... + 768291.

It is an arithmetic number, because the mean of its divisors is an integer number (193419828).

Almost surely, 2^1155912981 is an apocalyptic number.

It is an amenable number.

1155912981 is a deficient number, since it is larger than the sum of its proper divisors (391445643).

1155912981 is a wasteful number, since it uses less digits than its factorization.

1155912981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1535331.

The product of its digits is 32400, while the sum is 42.

The square root of 1155912981 is about 33998.7202847401. The cubic root of 1155912981 is about 1049.4821273874.

The spelling of 1155912981 in words is "one billion, one hundred fifty-five million, nine hundred twelve thousand, nine hundred eighty-one".