43309718675981 has 4 divisors (see below), whose sum is σ = 43310364568764. Its totient is φ = 43309072783200.

The previous prime is 43309718675947. The next prime is 43309718675987. The reversal of 43309718675981 is 18957681790334.

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 29679342015625 + 13630376660356 = 5447875^2 + 3691934^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43309718675981 is a prime.

It is a super-2 number, since 2×43309718675981² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43309718675987) 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, 322845800 + ... + 322979921.

It is an arithmetic number, because the mean of its divisors is an integer number (10827591142191).

Almost surely, 2^{43309718675981} is an apocalyptic number.

It is an amenable number.

43309718675981 is a deficient number, since it is larger than the sum of its proper divisors (645892783).

43309718675981 is an equidigital number, since it uses as much as digits as its factorization.

43309718675981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645892782.

The product of its (nonzero) digits is 274337280, while the sum is 71.

The spelling of 43309718675981 in words is "forty-three trillion, three hundred nine billion, seven hundred eighteen million, six hundred seventy-five thousand, nine hundred eighty-one".