1801872418 has 4 divisors (see below), whose sum is σ = 2702808630. Its totient is φ = 900936208.

The previous prime is 1801872407. The next prime is 1801872419. The reversal of 1801872418 is 8142781081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8142781081 = 103 ⋅79056127.

It can be written as a sum of positive squares in only one way, i.e., 1801747809 + 124609 = 42447^2 + 353^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1801872419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 450468103 + ... + 450468106.

Almost surely, 2^1801872418 is an apocalyptic number.

1801872418 is a deficient number, since it is larger than the sum of its proper divisors (900936212).

1801872418 is an equidigital number, since it uses as much as digits as its factorization.

1801872418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 900936211.

The product of its (nonzero) digits is 28672, while the sum is 40.

The square root of 1801872418 is about 42448.4677933138. The cubic root of 1801872418 is about 1216.8620464446.

The spelling of 1801872418 in words is "one billion, eight hundred one million, eight hundred seventy-two thousand, four hundred eighteen".