1816545970849 has 27 divisors (see below), whose sum is σ = 1892614065267. Its totient is φ = 1743505024800.

The previous prime is 1816545970829. The next prime is 1816545970859. The reversal of 1816545970849 is 9480795456181.

The square root of 1816545970849 is 1347793.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 87531364449 + 1729014606400 = 295857^2 + 1314920^2 .

It is not a de Polignac number, because 1816545970849 - 2¹¹ = 1816545968801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1816545970829) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3923425192 + ... + 3923425654.

Almost surely, 2^{1816545970849} is an apocalyptic number.

1816545970849 is the 1347793-rd square number.

1816545970849 is the 673897-th centered octagonal number.

It is an amenable number.

1816545970849 is a deficient number, since it is larger than the sum of its proper divisors (76068094418).

1816545970849 is an frugal number, since it uses more digits than its factorization.

1816545970849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1150 (or 575 counting only the distinct ones).

The product of its (nonzero) digits is 87091200, while the sum is 67.

The spelling of 1816545970849 in words is "one trillion, eight hundred sixteen billion, five hundred forty-five million, nine hundred seventy thousand, eight hundred forty-nine".