1018181909 has 8 divisors (see below), whose sum is σ = 1063723320. Its totient is φ = 973336000.

The previous prime is 1018181891. The next prime is 1018181921. The reversal of 1018181909 is 9091818101.

It can be written as a sum of positive squares in 4 ways, for example, as 702409009 + 315772900 = 26503^2 + 17770^2 .

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 1018181909 - 2¹⁶ = 1018116373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1018181009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 170882 + ... + 176739.

It is an arithmetic number, because the mean of its divisors is an integer number (132965415).

Almost surely, 2^1018181909 is an apocalyptic number.

It is an amenable number.

1018181909 is a deficient number, since it is larger than the sum of its proper divisors (45541411).

1018181909 is a wasteful number, since it uses less digits than its factorization.

1018181909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347751.

The product of its (nonzero) digits is 5184, while the sum is 38.

The square root of 1018181909 is about 31908.9628317813. The cubic root of 1018181909 is about 1006.0242716076.

The spelling of 1018181909 in words is "one billion, eighteen million, one hundred eighty-one thousand, nine hundred nine".