1218409718 has 4 divisors (see below), whose sum is σ = 1827614580.
Its totient is φ = 609204858.
The previous prime is 1218409691. The next prime is 1218409721. The reversal of 1218409718 is 8179048121.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8179048121 = 43321 ⋅188801.
It is a congruent number.
It is an unprimeable number.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 304602428 + ... + 304602431.
It is an arithmetic number, because the mean of its divisors is an integer number (456903645).
Almost surely, 21218409718 is an apocalyptic number.
1218409718 is a deficient number, since it is larger than the sum of its proper divisors (609204862).
1218409718 is an equidigital number, since it uses as much as digits as its factorization.
1218409718 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 609204861.
The product of its (nonzero) digits is 32256, while the sum is 41.
The square root of 1218409718 is about 34905.7261491578.
The cubic root of 1218409718 is about 1068.0652486005.
The spelling of 1218409718 in words is "one billion, two hundred eighteen million, four hundred nine thousand, seven hundred eighteen".