12665719385450 has 12 divisors (see below), whose sum is σ = 23558238057030. Its totient is φ = 5066287754160.

The previous prime is 12665719385381. The next prime is 12665719385471. The reversal of 12665719385450 is 5458391756621.

It is a Cunningham number, because it is equal to 3558893²+1.

It can be written as a sum of positive squares in 3 ways, for example, as 11672725072369 + 992994313081 = 3416537^2 + 996491^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 126657193805 + ... + 126657193904.

It is a 1-persistent number, because it is pandigital, but 2⋅12665719385450 = 25331438770900 is not.

Almost surely, 2^{12665719385450} is an apocalyptic number.

12665719385450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12665719385450 is a deficient number, since it is larger than the sum of its proper divisors (10892518671580).

12665719385450 is a wasteful number, since it uses less digits than its factorization.

12665719385450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253314387721 (or 253314387716 counting only the distinct ones).

The product of its (nonzero) digits is 54432000, while the sum is 62.

The spelling of 12665719385450 in words is "twelve trillion, six hundred sixty-five billion, seven hundred nineteen million, three hundred eighty-five thousand, four hundred fifty".