21147166 has 16 divisors (see below), whose sum is σ = 33242400. Its totient is φ = 10070368.

The previous prime is 21147163. The next prime is 21147169. The reversal of 21147166 is 66174112.

It is an interprime number because it is at equal distance from previous prime (21147163) and next prime (21147169).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21147163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11520 + ... + 13228.

It is an arithmetic number, because the mean of its divisors is an integer number (2077650).

Almost surely, 2^21147166 is an apocalyptic number.

21147166 is a deficient number, since it is larger than the sum of its proper divisors (12095234).

21147166 is a wasteful number, since it uses less digits than its factorization.

21147166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2003.

The product of its digits is 2016, while the sum is 28.

The square root of 21147166 is about 4598.6047884114. The cubic root of 21147166 is about 276.5353939259.

The spelling of 21147166 in words is "twenty-one million, one hundred forty-seven thousand, one hundred sixty-six".