1861318449 has 27 divisors (see below), whose sum is σ = 2739812673. Its totient is φ = 1217668032.

The previous prime is 1861318427. The next prime is 1861318453. The reversal of 1861318449 is 9448131681.

The square root of 1861318449 is 43143.

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

1861318449 is a `hidden beast` number, since 18 + 613 + 18 + 4 + 4 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 792028449 + 1069290000 = 28143^2 + 32700^2 .

It is not a de Polignac number, because 1861318449 - 2¹⁹ = 1860794161 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1861318469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 9448219 + ... + 9448415.

Almost surely, 2^1861318449 is an apocalyptic number.

1861318449 is the 43143-rd square number.

1861318449 is the 21572-nd centered octagonal number.

It is an amenable number.

1861318449 is a deficient number, since it is larger than the sum of its proper divisors (878494224).

1861318449 is an frugal number, since it uses more digits than its factorization.

1861318449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 546 (or 273 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The cubic root of 1861318449 is about 1230.0994585449.

The spelling of 1861318449 in words is "one billion, eight hundred sixty-one million, three hundred eighteen thousand, four hundred forty-nine".