1218920197 has 8 divisors (see below), whose sum is σ = 1330826112. Its totient is φ = 1107196800.

The previous prime is 1218920189. The next prime is 1218920207. The reversal of 1218920197 is 7910298121.

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 1218920197 - 2³ = 1218920189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218920107) 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, 31468 + ... + 58549.

It is an arithmetic number, because the mean of its divisors is an integer number (166353264).

Almost surely, 2^1218920197 is an apocalyptic number.

It is an amenable number.

1218920197 is a deficient number, since it is larger than the sum of its proper divisors (111905915).

1218920197 is a wasteful number, since it uses less digits than its factorization.

1218920197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91259.

The product of its (nonzero) digits is 18144, while the sum is 40.

The square root of 1218920197 is about 34913.0376363902. The cubic root of 1218920197 is about 1068.2143907555.

The spelling of 1218920197 in words is "one billion, two hundred eighteen million, nine hundred twenty thousand, one hundred ninety-seven".