1218990 has 32 divisors (see below), whose sum is σ = 2954880. Its totient is φ = 321824.

The previous prime is 1218989. The next prime is 1218991. The reversal of 1218990 is 998121.

It is an interprime number because it is at equal distance from previous prime (1218989) and next prime (1218991).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218991) 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 15 ways as a sum of consecutive naturals, for example, 5257 + ... + 5483.

It is an arithmetic number, because the mean of its divisors is an integer number (92340).

2^1218990 is an apocalyptic number.

1218990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1218990 is an abundant number, since it is smaller than the sum of its proper divisors (1735890).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1218990 is a wasteful number, since it uses less digits than its factorization.

1218990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 1218990 is about 1104.0788015355. The cubic root of 1218990 is about 106.8234781247.

The spelling of 1218990 in words is "one million, two hundred eighteen thousand, nine hundred ninety".