43623515561 has 2 divisors, whose sum is σ = 43623515562. Its totient is φ = 43623515560.

The previous prime is 43623515543. The next prime is 43623515581. The reversal of 43623515561 is 16551532634.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35411712400 + 8211803161 = 188180^2 + 90619^2 .

It is a cyclic number.

It is not a de Polignac number, because 43623515561 - 2¹⁸ = 43623253417 is a prime.

It is a super-2 number, since 2×43623515561² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (43623515581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21811757780 + 21811757781.

It is an arithmetic number, because the mean of its divisors is an integer number (21811757781).

Almost surely, 2^43623515561 is an apocalyptic number.

It is an amenable number.

43623515561 is a deficient number, since it is larger than the sum of its proper divisors (1).

43623515561 is an equidigital number, since it uses as much as digits as its factorization.

43623515561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 324000, while the sum is 41.

The spelling of 43623515561 in words is "forty-three billion, six hundred twenty-three million, five hundred fifteen thousand, five hundred sixty-one".