1851851818 has 8 divisors (see below), whose sum is σ = 2787594048. Its totient is φ = 922653804.

The previous prime is 1851851801. The next prime is 1851851851. The reversal of 1851851818 is 8181581581.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1635346 + ... + 1636477.

It is an arithmetic number, because the mean of its divisors is an integer number (348449256).

Almost surely, 2^1851851818 is an apocalyptic number.

1851851818 is a deficient number, since it is larger than the sum of its proper divisors (935742230).

1851851818 is a wasteful number, since it uses less digits than its factorization.

1851851818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3272108.

The product of its digits is 102400, while the sum is 46.

The square root of 1851851818 is about 43033.1478978705. The cubic root of 1851851818 is about 1228.0104920641.

It can be divided in two parts, 18 and 51851818, that added together give a triangular number (51851836 = T₁₀₁₈₃).

The spelling of 1851851818 in words is "one billion, eight hundred fifty-one million, eight hundred fifty-one thousand, eight hundred eighteen".