16866961 has 2 divisors, whose sum is σ = 16866962. Its totient is φ = 16866960.

The previous prime is 16866959. The next prime is 16866977. The reversal of 16866961 is 16966861.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14676561 + 2190400 = 3831^2 + 1480^2 .

It is an emirp because it is prime and its reverse (16966861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16866961 - 2¹ = 16866959 is a prime.

It is a super-3 number, since 3×16866961³ (a number of 23 digits) contains 333 as substring.

Together with 16866959, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16866901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8433480 + 8433481.

It is an arithmetic number, because the mean of its divisors is an integer number (8433481).

Almost surely, 2^16866961 is an apocalyptic number.

It is an amenable number.

16866961 is a deficient number, since it is larger than the sum of its proper divisors (1).

16866961 is an equidigital number, since it uses as much as digits as its factorization.

16866961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 43.

The square root of 16866961 is about 4106.9405888082. The cubic root of 16866961 is about 256.4556551716.

The spelling of 16866961 in words is "sixteen million, eight hundred sixty-six thousand, nine hundred sixty-one".