1155899 has 2 divisors, whose sum is σ = 1155900.
Its totient is φ = 1155898.
The previous prime is 1155863. The next prime is 1155901. The reversal of 1155899 is 9985511.
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 1155899 - 220 = 107323 is a prime.
It is a super-2 number, since 2×11558992 = 2672204996402, which contains 22 as substring.
Together with 1155901, it forms a pair of twin primes.
It is a Chen prime.
It is an Ulam number.
It is a plaindrome in base 10.
It is not a weakly prime, because it can be changed into another prime (1155829) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a good prime.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 577949 + 577950.
It is an arithmetic number, because the mean of its divisors is an integer number (577950).
21155899 is an apocalyptic number.
1155899 is a deficient number, since it is larger than the sum of its proper divisors (1).
1155899 is an equidigital number, since it uses as much as digits as its factorization.
1155899 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 16200, while the sum is 38.
The square root of 1155899 is about 1075.1274343072.
The cubic root of 1155899 is about 104.9477896138.
The spelling of 1155899 in words is "one million, one hundred fifty-five thousand, eight hundred ninety-nine".