39811821841 has 45 divisors (see below), whose sum is σ = 47004842145. Its totient is φ = 33712419840.

The previous prime is 39811821839. The next prime is 39811821851. The reversal of 39811821841 is 14812811893.

The square root of 39811821841 is 199529.

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

It can be written as a sum of positive squares in 4 ways, for example, as 2330861841 + 37480960000 = 48279^2 + 193600^2 .

It is not a de Polignac number, because 39811821841 - 2¹ = 39811821839 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 39811821791 and 39811821800.

It is not an unprimeable number, because it can be changed into a prime (39811821811) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 410431105 + ... + 410431201.

Almost surely, 2^39811821841 is an apocalyptic number.

39811821841 is the 199529-th square number.

39811821841 is the 99765-th centered octagonal number.

It is an amenable number.

39811821841 is a deficient number, since it is larger than the sum of its proper divisors (7193020304).

39811821841 is an frugal number, since it uses more digits than its factorization.

39811821841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272 (or 125 counting only the distinct ones).

The product of its digits is 110592, while the sum is 46.

The spelling of 39811821841 in words is "thirty-nine billion, eight hundred eleven million, eight hundred twenty-one thousand, eight hundred forty-one".