1218454009 has 2 divisors, whose sum is σ = 1218454010. Its totient is φ = 1218454008.

The previous prime is 1218454007. The next prime is 1218454019. The reversal of 1218454009 is 9004548121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1009015225 + 209438784 = 31765^2 + 14472^2 .

It is a cyclic number.

It is not a de Polignac number, because 1218454009 - 2¹ = 1218454007 is a prime.

Together with 1218454007, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1218454007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609227004 + 609227005.

It is an arithmetic number, because the mean of its divisors is an integer number (609227005).

Almost surely, 2^1218454009 is an apocalyptic number.

It is an amenable number.

1218454009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218454009 is an equidigital number, since it uses as much as digits as its factorization.

1218454009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 1218454009 is about 34906.3605808454. The cubic root of 1218454009 is about 1068.0781903622.

The spelling of 1218454009 in words is "one billion, two hundred eighteen million, four hundred fifty-four thousand, nine".