181818751844 has 6 divisors (see below), whose sum is σ = 318182815734. Its totient is φ = 90909375920.

The previous prime is 181818751841. The next prime is 181818751859. The reversal of 181818751844 is 448157818181.

It can be written as a sum of positive squares in only one way, i.e., 146564934244 + 35253817600 = 382838^2 + 187760^2 .

It is a super-2 number, since 2×181818751844² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 181818751844.

It is not an unprimeable number, because it can be changed into a prime (181818751841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22727343977 + ... + 22727343984.

It is an arithmetic number, because the mean of its divisors is an integer number (53030469289).

Almost surely, 2^181818751844 is an apocalyptic number.

It is an amenable number.

181818751844 is a deficient number, since it is larger than the sum of its proper divisors (136364063890).

181818751844 is a wasteful number, since it uses less digits than its factorization.

181818751844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45454687965 (or 45454687963 counting only the distinct ones).

The product of its digits is 2293760, while the sum is 56.

The spelling of 181818751844 in words is "one hundred eighty-one billion, eight hundred eighteen million, seven hundred fifty-one thousand, eight hundred forty-four".