1918148909 has 2 divisors, whose sum is σ = 1918148910. Its totient is φ = 1918148908.

The previous prime is 1918148893. The next prime is 1918148951. The reversal of 1918148909 is 9098418191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1600240009 + 317908900 = 40003^2 + 17830^2 .

It is a cyclic number.

It is not a de Polignac number, because 1918148909 - 2⁴ = 1918148893 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1918148959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 959074454 + 959074455.

It is an arithmetic number, because the mean of its divisors is an integer number (959074455).

Almost surely, 2^1918148909 is an apocalyptic number.

It is an amenable number.

1918148909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1918148909 is an equidigital number, since it uses as much as digits as its factorization.

1918148909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 50.

The square root of 1918148909 is about 43796.6769173187. The cubic root of 1918148909 is about 1242.4934454674.

The spelling of 1918148909 in words is "one billion, nine hundred eighteen million, one hundred forty-eight thousand, nine hundred nine".