16921038563361 has 27 divisors (see below), whose sum is σ = 25795957326321. Its totient is φ = 10686823637544.

The previous prime is 16921038563329. The next prime is 16921038563441. The reversal of 16921038563361 is 16336583012961.

The square root of 16921038563361 is 4113519.

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

16921038563361 is a `hidden beast` number, since 1 + 6 + 9 + 2 + 10 + 3 + 8 + 563 + 3 + 61 = 666.

It is not a de Polignac number, because 16921038563361 - 2⁵ = 16921038563329 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16921038563298 and 16921038563307.

It is not an unprimeable number, because it can be changed into a prime (16921038562361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 234434500 + ... + 234506666.

Almost surely, 2^{16921038563361} is an apocalyptic number.

16921038563361 is the 4113519-th square number.

16921038563361 is the 2056760-th centered octagonal number.

It is an amenable number.

16921038563361 is a deficient number, since it is larger than the sum of its proper divisors (8874918762960).

16921038563361 is an frugal number, since it uses more digits than its factorization.

16921038563361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144378 (or 72189 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 54.

The spelling of 16921038563361 in words is "sixteen trillion, nine hundred twenty-one billion, thirty-eight million, five hundred sixty-three thousand, three hundred sixty-one".