1218993 has 4 divisors (see below), whose sum is σ = 1625328. Its totient is φ = 812660.

The previous prime is 1218991. The next prime is 1219003. The reversal of 1218993 is 3998121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1218993 - 2¹ = 1218991 is a prime.

It is a D-number.

1218993 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1218991) 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, 203163 + ... + 203168.

It is an arithmetic number, because the mean of its divisors is an integer number (406332).

2^1218993 is an apocalyptic number.

It is an amenable number.

1218993 is a deficient number, since it is larger than the sum of its proper divisors (406335).

1218993 is an equidigital number, since it uses as much as digits as its factorization.

1218993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406334.

The product of its digits is 3888, while the sum is 33.

The square root of 1218993 is about 1104.0801601333. The cubic root of 1218993 is about 106.8235657574.

It can be divided in two parts, 1218 and 993, that added together give a triangular number (2211 = T₆₆).

The spelling of 1218993 in words is "one million, two hundred eighteen thousand, nine hundred ninety-three".