1918192118393 has 4 divisors (see below), whose sum is σ = 1920093201780. Its totient is φ = 1916291035008.

The previous prime is 1918192118363. The next prime is 1918192118417. The reversal of 1918192118393 is 3938112918191.

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 199177441849 + 1719014676544 = 446293^2 + 1311112^2 .

It is a cyclic number.

It is not a de Polignac number, because 1918192118393 - 2¹² = 1918192114297 is a prime.

It is a super-3 number, since 3×1918192118393³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1918192118363) 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, 950540180 + ... + 950542197.

It is an arithmetic number, because the mean of its divisors is an integer number (480023300445).

Almost surely, 2^{1918192118393} is an apocalyptic number.

It is an amenable number.

1918192118393 is a deficient number, since it is larger than the sum of its proper divisors (1901083387).

1918192118393 is a wasteful number, since it uses less digits than its factorization.

1918192118393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1901083386.

The product of its digits is 839808, while the sum is 56.

The spelling of 1918192118393 in words is "one trillion, nine hundred eighteen billion, one hundred ninety-two million, one hundred eighteen thousand, three hundred ninety-three".