1815844273844 has 6 divisors (see below), whose sum is σ = 3177727479234. Its totient is φ = 907922136920.

The previous prime is 1815844273801. The next prime is 1815844273861. The reversal of 1815844273844 is 4483724485181.

It can be written as a sum of positive squares in only one way, i.e., 1207335068944 + 608509204900 = 1098788^2 + 780070^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 226980534227 + ... + 226980534234.

It is an arithmetic number, because the mean of its divisors is an integer number (529621246539).

Almost surely, 2^{1815844273844} is an apocalyptic number.

It is an amenable number.

1815844273844 is a deficient number, since it is larger than the sum of its proper divisors (1361883205390).

1815844273844 is a wasteful number, since it uses less digits than its factorization.

1815844273844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453961068465 (or 453961068463 counting only the distinct ones).

The product of its digits is 27525120, while the sum is 59.

The spelling of 1815844273844 in words is "one trillion, eight hundred fifteen billion, eight hundred forty-four million, two hundred seventy-three thousand, eight hundred forty-four".