1218290 has 16 divisors (see below), whose sum is σ = 2269080. Its totient is φ = 470400.

The previous prime is 1218281. The next prime is 1218307. The reversal of 1218290 is 928121.

It can be written as a sum of positive squares in 4 ways, for example, as 683929 + 534361 = 827^2 + 731^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1811 + ... + 2390.

2^1218290 is an apocalyptic number.

1218290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1218290 is a deficient number, since it is larger than the sum of its proper divisors (1050790).

1218290 is a wasteful number, since it uses less digits than its factorization.

1218290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4237.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 1218290 is about 1103.7617496543. The cubic root of 1218290 is about 106.8030265616.

It can be divided in two parts, 1218 and 290, that multiplied together give a triangular number (353220 = T₈₄₀).

The spelling of 1218290 in words is "one million, two hundred eighteen thousand, two hundred ninety".