16968521 has 2 divisors, whose sum is σ = 16968522. Its totient is φ = 16968520.

The previous prime is 16968517. The next prime is 16968557. The reversal of 16968521 is 12586961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11155600 + 5812921 = 3340^2 + 2411^2 .

It is a cyclic number.

It is not a de Polignac number, because 16968521 - 2² = 16968517 is a prime.

It is not a weakly prime, because it can be changed into another prime (16968421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8484260 + 8484261.

It is an arithmetic number, because the mean of its divisors is an integer number (8484261).

Almost surely, 2^16968521 is an apocalyptic number.

It is an amenable number.

16968521 is a deficient number, since it is larger than the sum of its proper divisors (1).

16968521 is an equidigital number, since it uses as much as digits as its factorization.

16968521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 38.

The square root of 16968521 is about 4119.2864673387. The cubic root of 16968521 is about 256.9693524295.

The spelling of 16968521 in words is "sixteen million, nine hundred sixty-eight thousand, five hundred twenty-one".