1638115474117 has 4 divisors (see below), whose sum is σ = 1638206050860. Its totient is φ = 1638024897376.

The previous prime is 1638115474109. The next prime is 1638115474139. The reversal of 1638115474117 is 7114745118361.

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 647789961316 + 990325512801 = 804854^2 + 995151^2 .

It is a cyclic number.

It is not a de Polignac number, because 1638115474117 - 2³ = 1638115474109 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 (1638115474147) 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, 45261238 + ... + 45297415.

It is an arithmetic number, because the mean of its divisors is an integer number (409551512715).

Almost surely, 2^{1638115474117} is an apocalyptic number.

It is an amenable number.

1638115474117 is a deficient number, since it is larger than the sum of its proper divisors (90576743).

1638115474117 is an equidigital number, since it uses as much as digits as its factorization.

1638115474117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90576742.

The product of its digits is 564480, while the sum is 49.

The spelling of 1638115474117 in words is "one trillion, six hundred thirty-eight billion, one hundred fifteen million, four hundred seventy-four thousand, one hundred seventeen".