1043665242561 has 10 divisors (see below), whose sum is σ = 1559055485922. Its totient is φ = 695776828320.

The previous prime is 1043665242517. The next prime is 1043665242563. The reversal of 1043665242561 is 1652425663401.

1043665242561 is a `hidden beast` number, since 1 + 0 + 4 + 3 + 6 + 65 + 24 + 2 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1034289000000 + 9376242561 = 1017000^2 + 96831^2 .

It is not a de Polignac number, because 1043665242561 - 2¹³ = 1043665234369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1043665242563) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 6442377960 + ... + 6442378121.

Almost surely, 2^{1043665242561} is an apocalyptic number.

It is an amenable number.

1043665242561 is a deficient number, since it is larger than the sum of its proper divisors (515390243361).

1043665242561 is an equidigital number, since it uses as much as digits as its factorization.

1043665242561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12884756093 (or 12884756084 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 45.

The spelling of 1043665242561 in words is "one trillion, forty-three billion, six hundred sixty-five million, two hundred forty-two thousand, five hundred sixty-one".