3121861818 has 8 divisors (see below), whose sum is σ = 6243723648. Its totient is φ = 1040620604.

The previous prime is 3121861807. The next prime is 3121861837. The reversal of 3121861818 is 8181681213.

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

3121861818 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 260155146 + ... + 260155157.

It is an arithmetic number, because the mean of its divisors is an integer number (780465456).

Almost surely, 2^3121861818 is an apocalyptic number.

3121861818 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

3121861818 is a wasteful number, since it uses less digits than its factorization.

3121861818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520310308.

The product of its digits is 18432, while the sum is 39.

The square root of 3121861818 is about 55873.6236340547. The cubic root of 3121861818 is about 1461.5193132051.

The spelling of 3121861818 in words is "three billion, one hundred twenty-one million, eight hundred sixty-one thousand, eight hundred eighteen".