1818191910001 has 4 divisors (see below), whose sum is σ = 1818205436404. Its totient is φ = 1818178383600.

The previous prime is 1818191909993. The next prime is 1818191910053. The reversal of 1818191910001 is 1000191918181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 817839879025 + 1000352030976 = 904345^2 + 1000176^2 .

It is a cyclic number.

It is not a de Polignac number, because 1818191910001 - 2³ = 1818191909993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1818191940001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6559530 + ... + 6831091.

It is an arithmetic number, because the mean of its divisors is an integer number (454551359101).

Almost surely, 2^{1818191910001} is an apocalyptic number.

It is an amenable number.

1818191910001 is a deficient number, since it is larger than the sum of its proper divisors (13526403).

1818191910001 is a wasteful number, since it uses less digits than its factorization.

1818191910001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13526402.

The product of its (nonzero) digits is 5184, while the sum is 40.

The spelling of 1818191910001 in words is "one trillion, eight hundred eighteen billion, one hundred ninety-one million, nine hundred ten thousand, one".