1218987 has 24 divisors (see below), whose sum is σ = 2196480. Its totient is φ = 632880.

The previous prime is 1218953. The next prime is 1218989. The reversal of 1218987 is 7898121.

It is not a de Polignac number, because 1218987 - 2⁶ = 1218923 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (1218989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 187 + ... + 1572.

It is an arithmetic number, because the mean of its divisors is an integer number (91520).

2^1218987 is an apocalyptic number.

1218987 is a deficient number, since it is larger than the sum of its proper divisors (977493).

1218987 is a wasteful number, since it uses less digits than its factorization.

1218987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783 (or 1780 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 1218987 is about 1104.0774429360. The cubic root of 1218987 is about 106.8233904919.

The spelling of 1218987 in words is "one million, two hundred eighteen thousand, nine hundred eighty-seven".