1161987 has 4 divisors (see below), whose sum is σ = 1549320. Its totient is φ = 774656.

The previous prime is 1161949. The next prime is 1161991. The reversal of 1161987 is 7891611.

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

It is a cyclic number.

It is not a de Polignac number, because 1161987 - 2¹⁶ = 1096451 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (1161947) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193662 + ... + 193667.

It is an arithmetic number, because the mean of its divisors is an integer number (387330).

2^1161987 is an apocalyptic number.

1161987 is a deficient number, since it is larger than the sum of its proper divisors (387333).

1161987 is an equidigital number, since it uses as much as digits as its factorization.

1161987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387332.

The product of its digits is 3024, while the sum is 33.

The square root of 1161987 is about 1077.9550083375. The cubic root of 1161987 is about 105.1317167855.

The spelling of 1161987 in words is "one million, one hundred sixty-one thousand, nine hundred eighty-seven".