1155987 has 24 divisors (see below), whose sum is σ = 1946880. Its totient is φ = 647280.

The previous prime is 1155977. The next prime is 1155997. The reversal of 1155987 is 7895511.

It is an interprime number because it is at equal distance from previous prime (1155977) and next prime (1155997).

It is not a de Polignac number, because 1155987 - 2⁴ = 1155971 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1155907) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3562 + ... + 3872.

It is an arithmetic number, because the mean of its divisors is an integer number (81120).

2^1155987 is an apocalyptic number.

1155987 is a deficient number, since it is larger than the sum of its proper divisors (790893).

1155987 is a wasteful number, since it uses less digits than its factorization.

1155987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383 (or 380 counting only the distinct ones).

The product of its digits is 12600, while the sum is 36.

The square root of 1155987 is about 1075.1683589094. The cubic root of 1155987 is about 104.9504528139.

The spelling of 1155987 in words is "one million, one hundred fifty-five thousand, nine hundred eighty-seven".