43839978961 has 4 divisors (see below), whose sum is σ = 44440526692. Its totient is φ = 43239431232.

The previous prime is 43839978953. The next prime is 43839978967. The reversal of 43839978961 is 16987993834.

43839978961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35781505600 + 8058473361 = 189160^2 + 89769^2 .

It is a cyclic number.

It is not a de Polignac number, because 43839978961 - 2³ = 43839978953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43839978967) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 300273756 + ... + 300273901.

It is an arithmetic number, because the mean of its divisors is an integer number (11110131673).

Almost surely, 2^43839978961 is an apocalyptic number.

It is an amenable number.

43839978961 is a deficient number, since it is larger than the sum of its proper divisors (600547731).

43839978961 is an equidigital number, since it uses as much as digits as its factorization.

43839978961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600547730.

The product of its digits is 70543872, while the sum is 67.

The spelling of 43839978961 in words is "forty-three billion, eight hundred thirty-nine million, nine hundred seventy-eight thousand, nine hundred sixty-one".