16861517 has 2 divisors, whose sum is σ = 16861518. Its totient is φ = 16861516.

The previous prime is 16861483. The next prime is 16861519. The reversal of 16861517 is 71516861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16370116 + 491401 = 4046^2 + 701^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16861517 is a prime.

Together with 16861519, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16861519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8430758 + 8430759.

It is an arithmetic number, because the mean of its divisors is an integer number (8430759).

Almost surely, 2^16861517 is an apocalyptic number.

It is an amenable number.

16861517 is a deficient number, since it is larger than the sum of its proper divisors (1).

16861517 is an equidigital number, since it uses as much as digits as its factorization.

16861517 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 35.

The square root of 16861517 is about 4106.2777548529. The cubic root of 16861517 is about 256.4280608938.

The spelling of 16861517 in words is "sixteen million, eight hundred sixty-one thousand, five hundred seventeen".