1218289197 has 8 divisors (see below), whose sum is σ = 1631358144. Its totient is φ = 808706528.

The previous prime is 1218289187. The next prime is 1218289229. The reversal of 1218289197 is 7919828121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1218289197 - 2⁷ = 1218289069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218289187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 870753 + ... + 872150.

It is an arithmetic number, because the mean of its divisors is an integer number (203919768).

Almost surely, 2^1218289197 is an apocalyptic number.

It is an amenable number.

1218289197 is a deficient number, since it is larger than the sum of its proper divisors (413068947).

1218289197 is a wasteful number, since it uses less digits than its factorization.

1218289197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1743139.

The product of its digits is 145152, while the sum is 48.

The square root of 1218289197 is about 34903.9997278249. Note that the first 3 decimals coincide. The cubic root of 1218289197 is about 1068.0300309627.

The spelling of 1218289197 in words is "one billion, two hundred eighteen million, two hundred eighty-nine thousand, one hundred ninety-seven".