1812115801 has 4 divisors (see below), whose sum is σ = 1813088272. Its totient is φ = 1811143332.

The previous prime is 1812115769. The next prime is 1812115813. The reversal of 1812115801 is 1085112181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1085112181 = 43 ⋅25235167.

It is a cyclic number.

It is not a de Polignac number, because 1812115801 - 2⁵ = 1812115769 is a prime.

It is a super-3 number, since 3×1812115801³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1812115801.

It is not an unprimeable number, because it can be changed into a prime (1812115871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 483435 + ... + 487168.

It is an arithmetic number, because the mean of its divisors is an integer number (453272068).

Almost surely, 2^1812115801 is an apocalyptic number.

It is an amenable number.

1812115801 is a deficient number, since it is larger than the sum of its proper divisors (972471).

1812115801 is an equidigital number, since it uses as much as digits as its factorization.

1812115801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 972470.

The product of its (nonzero) digits is 640, while the sum is 28.

The square root of 1812115801 is about 42568.9534872541. The cubic root of 1812115801 is about 1219.1635853013.

Adding to 1812115801 its reverse (1085112181), we get a palindrome (2897227982).

The spelling of 1812115801 in words is "one billion, eight hundred twelve million, one hundred fifteen thousand, eight hundred one".