243861415591 has 2 divisors, whose sum is σ = 243861415592. Its totient is φ = 243861415590.

The previous prime is 243861415559. The next prime is 243861415619. The reversal of 243861415591 is 195514168342.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 243861415591 - 2⁵ = 243861415559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243861815591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121930707795 + 121930707796.

It is an arithmetic number, because the mean of its divisors is an integer number (121930707796).

Almost surely, 2^243861415591 is an apocalyptic number.

243861415591 is a deficient number, since it is larger than the sum of its proper divisors (1).

243861415591 is an equidigital number, since it uses as much as digits as its factorization.

243861415591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1036800, while the sum is 49.

The spelling of 243861415591 in words is "two hundred forty-three billion, eight hundred sixty-one million, four hundred fifteen thousand, five hundred ninety-one".