43947613891 has 4 divisors (see below), whose sum is σ = 43998895512. Its totient is φ = 43896332272.

The previous prime is 43947613877. The next prime is 43947613901. The reversal of 43947613891 is 19831674934.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19831674934 = 2 ⋅9915837467.

It is a cyclic number.

It is not a de Polignac number, because 43947613891 - 2¹⁷ = 43947482819 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43947611891) 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, 25639525 + ... + 25641238.

It is an arithmetic number, because the mean of its divisors is an integer number (10999723878).

Almost surely, 2^43947613891 is an apocalyptic number.

43947613891 is a deficient number, since it is larger than the sum of its proper divisors (51281621).

43947613891 is an equidigital number, since it uses as much as digits as its factorization.

43947613891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51281620.

The product of its digits is 3919104, while the sum is 55.

The spelling of 43947613891 in words is "forty-three billion, nine hundred forty-seven million, six hundred thirteen thousand, eight hundred ninety-one".