1155999998 has 4 divisors (see below), whose sum is σ = 1734000000. Its totient is φ = 577999998.

The previous prime is 1155999989. The next prime is 1156000037. The reversal of 1155999998 is 8999995511.

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

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 288999998 + ... + 289000001.

It is an arithmetic number, because the mean of its divisors is an integer number (433500000).

Almost surely, 2^1155999998 is an apocalyptic number.

1155999998 is a deficient number, since it is larger than the sum of its proper divisors (578000002).

1155999998 is an equidigital number, since it uses as much as digits as its factorization.

1155999998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 578000001.

The product of its digits is 11809800, while the sum is 65.

The square root of 1155999998 is about 33999.9999705882. Note that the first 4 decimals coincide. The cubic root of 1155999998 is about 1049.5084616924.

The spelling of 1155999998 in words is "one billion, one hundred fifty-five million, nine hundred ninety-nine thousand, nine hundred ninety-eight".