18581725310909 has 2 divisors, whose sum is σ = 18581725310910. Its totient is φ = 18581725310908.

The previous prime is 18581725310849. The next prime is 18581725310927. The reversal of 18581725310909 is 90901352718581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12145204090009 + 6436521220900 = 3484997^2 + 2537030^2 .

It is a cyclic number.

It is not a de Polignac number, because 18581725310909 - 2¹⁶ = 18581725245373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18581725310959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9290862655454 + 9290862655455.

It is an arithmetic number, because the mean of its divisors is an integer number (9290862655455).

Almost surely, 2^{18581725310909} is an apocalyptic number.

It is an amenable number.

18581725310909 is a deficient number, since it is larger than the sum of its proper divisors (1).

18581725310909 is an equidigital number, since it uses as much as digits as its factorization.

18581725310909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5443200, while the sum is 59.

The spelling of 18581725310909 in words is "eighteen trillion, five hundred eighty-one billion, seven hundred twenty-five million, three hundred ten thousand, nine hundred nine".