1218910673 has 4 divisors (see below), whose sum is σ = 1220630580. Its totient is φ = 1217190768.

The previous prime is 1218910657. The next prime is 1218910709. The reversal of 1218910673 is 3760198121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3760198121 = 149 ⋅25236229.

It can be written as a sum of positive squares in 2 ways, for example, as 237529744 + 981380929 = 15412^2 + 31327^2 .

It is a cyclic number.

It is not a de Polignac number, because 1218910673 - 2⁴ = 1218910657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1218910603) 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, 858890 + ... + 860307.

It is an arithmetic number, because the mean of its divisors is an integer number (305157645).

Almost surely, 2^1218910673 is an apocalyptic number.

It is an amenable number.

1218910673 is a deficient number, since it is larger than the sum of its proper divisors (1719907).

1218910673 is an equidigital number, since it uses as much as digits as its factorization.

1218910673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719906.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 1218910673 is about 34912.9012400860. The cubic root of 1218910673 is about 1068.2116085935.

The spelling of 1218910673 in words is "one billion, two hundred eighteen million, nine hundred ten thousand, six hundred seventy-three".