43681993544 has 48 divisors (see below), whose sum is σ = 100880249580. Its totient is φ = 17619624960.

The previous prime is 43681993541. The next prime is 43681993547. The reversal of 43681993544 is 44539918634.

It is an interprime number because it is at equal distance from previous prime (43681993541) and next prime (43681993547).

It can be written as a sum of positive squares in 2 ways, for example, as 34498604644 + 9183388900 = 185738^2 + 95830^2 .

It is a Harshad number since it is a multiple of its sum of digits (56).

It is a self number, because there is not a number n which added to its sum of digits gives 43681993544.

It is not an unprimeable number, because it can be changed into a prime (43681993541) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3270797 + ... + 3284124.

Almost surely, 2^43681993544 is an apocalyptic number.

It is an amenable number.

43681993544 is an abundant number, since it is smaller than the sum of its proper divisors (57198256036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

43681993544 is a wasteful number, since it uses less digits than its factorization.

43681993544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6554958 (or 6554947 counting only the distinct ones).

The product of its digits is 11197440, while the sum is 56.

The spelling of 43681993544 in words is "forty-three billion, six hundred eighty-one million, nine hundred ninety-three thousand, five hundred forty-four".