1218545 has 4 divisors (see below), whose sum is σ = 1462260. Its totient is φ = 974832.

The previous prime is 1218533. The next prime is 1218557. The reversal of 1218545 is 5458121.

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

It is an interprime number because it is at equal distance from previous prime (1218533) and next prime (1218557).

It can be written as a sum of positive squares in 2 ways, for example, as 485809 + 732736 = 697^2 + 856^2 .

It is a cyclic number.

It is not a de Polignac number, because 1218545 - 2¹⁰ = 1217521 is a prime.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121850 + ... + 121859.

It is an arithmetic number, because the mean of its divisors is an integer number (365565).

2^1218545 is an apocalyptic number.

It is an amenable number.

1218545 is a deficient number, since it is larger than the sum of its proper divisors (243715).

1218545 is an equidigital number, since it uses as much as digits as its factorization.

1218545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243714.

The product of its digits is 1600, while the sum is 26.

The square root of 1218545 is about 1103.8772576695. The cubic root of 1218545 is about 106.8104776808.

The spelling of 1218545 in words is "one million, two hundred eighteen thousand, five hundred forty-five".