1218920123 has 2 divisors, whose sum is σ = 1218920124. Its totient is φ = 1218920122.

The previous prime is 1218920107. The next prime is 1218920147. The reversal of 1218920123 is 3210298121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1218920123 - 2⁴ = 1218920107 is a prime.

It is not a weakly prime, because it can be changed into another prime (1218920323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609460061 + 609460062.

It is an arithmetic number, because the mean of its divisors is an integer number (609460062).

Almost surely, 2^1218920123 is an apocalyptic number.

1218920123 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218920123 is an equidigital number, since it uses as much as digits as its factorization.

1218920123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 1218920123 is about 34913.0365766142. The cubic root of 1218920123 is about 1068.2143691386.

The spelling of 1218920123 in words is "one billion, two hundred eighteen million, nine hundred twenty thousand, one hundred twenty-three".