13944018120561 has 135 divisors (see below), whose sum is σ = 22071333089559. Its totient is φ = 8483076020736.

The previous prime is 13944018120559. The next prime is 13944018120577. The reversal of 13944018120561 is 16502181044931.

The square root of 13944018120561 is 3734169.

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

13944018120561 is a `hidden beast` number, since 1 + 3 + 9 + 4 + 4 + 0 + 1 + 81 + 2 + 0 + 561 = 666.

It can be written as a sum of positive squares in 7 ways, for example, as 222505607025 + 13721512513536 = 471705^2 + 3704256^2 .

It is not a de Polignac number, because 13944018120561 - 2¹ = 13944018120559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13944018128561) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 191013946821 + ... + 191013946893.

Almost surely, 2^{13944018120561} is an apocalyptic number.

13944018120561 is the 3734169-th square number.

13944018120561 is the 1867085-th centered octagonal number.

It is an amenable number.

13944018120561 is a deficient number, since it is larger than the sum of its proper divisors (8127314968998).

13944018120561 is an frugal number, since it uses more digits than its factorization.

13944018120561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 13944018120561 in words is "thirteen trillion, nine hundred forty-four billion, eighteen million, one hundred twenty thousand, five hundred sixty-one".