15581744161 has 2 divisors, whose sum is σ = 15581744162. Its totient is φ = 15581744160.

The previous prime is 15581744147. The next prime is 15581744237. The reversal of 15581744161 is 16144718551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15489295936 + 92448225 = 124456^2 + 9615^2 .

It is a cyclic number.

It is not a de Polignac number, because 15581744161 - 2¹³ = 15581735969 is a prime.

It is not a weakly prime, because it can be changed into another prime (15581742161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7790872080 + 7790872081.

It is an arithmetic number, because the mean of its divisors is an integer number (7790872081).

Almost surely, 2^15581744161 is an apocalyptic number.

It is an amenable number.

15581744161 is a deficient number, since it is larger than the sum of its proper divisors (1).

15581744161 is an equidigital number, since it uses as much as digits as its factorization.

15581744161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 134400, while the sum is 43.

The spelling of 15581744161 in words is "fifteen billion, five hundred eighty-one million, seven hundred forty-four thousand, one hundred sixty-one".