1218123361 has 32 divisors (see below), whose sum is σ = 1545813248. Its totient is φ = 934053120.

The previous prime is 1218123359. The next prime is 1218123367. The reversal of 1218123361 is 1633218121.

It is a happy number.

It is not a de Polignac number, because 1218123361 - 2¹ = 1218123359 is a prime.

It is a super-2 number, since 2×1218123361² = 2967649045227872642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1218123367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1113931 + ... + 1115023.

It is an arithmetic number, because the mean of its divisors is an integer number (48306664).

Almost surely, 2^1218123361 is an apocalyptic number.

It is an amenable number.

1218123361 is a deficient number, since it is larger than the sum of its proper divisors (327689887).

1218123361 is a wasteful number, since it uses less digits than its factorization.

1218123361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1481.

The product of its digits is 1728, while the sum is 28.

The square root of 1218123361 is about 34901.6240453077. The cubic root of 1218123361 is about 1067.9815679580.

The spelling of 1218123361 in words is "one billion, two hundred eighteen million, one hundred twenty-three thousand, three hundred sixty-one".