13666662954025 has 9 divisors (see below), whose sum is σ = 16946684983461. Its totient is φ = 10933315575840.

The previous prime is 13666662954023. The next prime is 13666662954041. The reversal of 13666662954025 is 52045926666631.

The square root of 13666662954025 is 3696845.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 5389468569 + 13661273485456 = 73413^2 + 3696116^2 .

It is not a de Polignac number, because 13666662954025 - 2¹ = 13666662954023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13666662954023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 18114541 + ... + 18853909.

Almost surely, 2^{13666662954025} is an apocalyptic number.

13666662954025 is the 3696845-th square number.

13666662954025 is the 1848423-rd centered octagonal number.

It is an amenable number.

13666662954025 is a deficient number, since it is larger than the sum of its proper divisors (3280022029436).

13666662954025 is an frugal number, since it uses more digits than its factorization.

13666662954025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1478748 (or 739374 counting only the distinct ones).

The product of its (nonzero) digits is 83980800, while the sum is 61.

The spelling of 13666662954025 in words is "thirteen trillion, six hundred sixty-six billion, six hundred sixty-two million, nine hundred fifty-four thousand, twenty-five".