21713166 has 24 divisors (see below), whose sum is σ = 47276424. Its totient is φ = 7202160.

The previous prime is 21713161. The next prime is 21713171. The reversal of 21713166 is 66131712.

It is an interprime number because it is at equal distance from previous prime (21713161) and next prime (21713171).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21713161) 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 in 11 ways as a sum of consecutive naturals, for example, 940 + ... + 6656.

It is an arithmetic number, because the mean of its divisors is an integer number (1969851).

Almost surely, 2^21713166 is an apocalyptic number.

21713166 is an abundant number, since it is smaller than the sum of its proper divisors (25563258).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21713166 is a wasteful number, since it uses less digits than its factorization.

21713166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5936 (or 5933 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 21713166 is about 4659.7388338833. The cubic root of 21713166 is about 278.9808442546.

Adding to 21713166 its reverse (66131712), we get a palindrome (87844878).

The spelling of 21713166 in words is "twenty-one million, seven hundred thirteen thousand, one hundred sixty-six".