1816138212 has 24 divisors (see below), whose sum is σ = 4843035456. Its totient is φ = 518896608.

The previous prime is 1816138201. The next prime is 1816138217. The reversal of 1816138212 is 2128316181.

It is not an unprimeable number, because it can be changed into a prime (1816138217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10810263 + ... + 10810430.

It is an arithmetic number, because the mean of its divisors is an integer number (201793144).

Almost surely, 2^1816138212 is an apocalyptic number.

1816138212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1816138212 is an abundant number, since it is smaller than the sum of its proper divisors (3026897244).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1816138212 is a wasteful number, since it uses less digits than its factorization.

1816138212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21620707 (or 21620705 counting only the distinct ones).

The product of its digits is 4608, while the sum is 33.

The square root of 1816138212 is about 42616.1731271122. The cubic root of 1816138212 is about 1220.0649907150.

The spelling of 1816138212 in words is "one billion, eight hundred sixteen million, one hundred thirty-eight thousand, two hundred twelve".