8181823181850 has 72 divisors (see below), whose sum is σ = 21985194007452. Its totient is φ = 2181485779200.

The previous prime is 8181823181839. The next prime is 8181823181881. The reversal of 8181823181850 is 581813281818.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 3660284496969 + 4521538684881 = 1913187^2 + 2126391^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1561560 + ... + 4336140.

Almost surely, 2^{8181823181850} is an apocalyptic number.

8181823181850 is an abundant number, since it is smaller than the sum of its proper divisors (13803370825602).

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

8181823181850 is a wasteful number, since it uses less digits than its factorization.

8181823181850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2781152 (or 2781144 counting only the distinct ones).

The product of its (nonzero) digits is 983040, while the sum is 54.

The spelling of 8181823181850 in words is "eight trillion, one hundred eighty-one billion, eight hundred twenty-three million, one hundred eighty-one thousand, eight hundred fifty".