1155312505 has 4 divisors (see below), whose sum is σ = 1386375012. Its totient is φ = 924250000.

The previous prime is 1155312493. The next prime is 1155312553. The reversal of 1155312505 is 5052135511.

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 910108224 + 245204281 = 30168^2 + 15659^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1155312505 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 (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115531246 + ... + 115531255.

It is an arithmetic number, because the mean of its divisors is an integer number (346593753).

Almost surely, 2^1155312505 is an apocalyptic number.

It is an amenable number.

1155312505 is a deficient number, since it is larger than the sum of its proper divisors (231062507).

1155312505 is an equidigital number, since it uses as much as digits as its factorization.

1155312505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231062506.

The product of its (nonzero) digits is 3750, while the sum is 28.

The square root of 1155312505 is about 33989.8882757799. Note that the first 3 decimals coincide. The cubic root of 1155312505 is about 1049.3003668813.

The spelling of 1155312505 in words is "one billion, one hundred fifty-five million, three hundred twelve thousand, five hundred five".