1218457155 has 8 divisors (see below), whose sum is σ = 1949531472. Its totient is φ = 649843808.

The previous prime is 1218457151. The next prime is 1218457157. The reversal of 1218457155 is 5517548121.

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 1218457155 - 2² = 1218457151 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1218457151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40615224 + ... + 40615253.

It is an arithmetic number, because the mean of its divisors is an integer number (243691434).

Almost surely, 2^1218457155 is an apocalyptic number.

1218457155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1218457155 is a deficient number, since it is larger than the sum of its proper divisors (731074317).

1218457155 is an equidigital number, since it uses as much as digits as its factorization.

1218457155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81230485.

The product of its digits is 56000, while the sum is 39.

The square root of 1218457155 is about 34906.4056442367. The cubic root of 1218457155 is about 1068.0791096066.

The spelling of 1218457155 in words is "one billion, two hundred eighteen million, four hundred fifty-seven thousand, one hundred fifty-five".