21342166 has 8 divisors (see below), whose sum is σ = 32418720. Its totient is φ = 10535928.

The previous prime is 21342163. The next prime is 21342169. The reversal of 21342166 is 66124312.

It is an interprime number because it is at equal distance from previous prime (21342163) and next prime (21342169).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21342166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21342161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67381 + ... + 67696.

It is an arithmetic number, because the mean of its divisors is an integer number (4052340).

Almost surely, 2^21342166 is an apocalyptic number.

21342166 is a deficient number, since it is larger than the sum of its proper divisors (11076554).

21342166 is a wasteful number, since it uses less digits than its factorization.

21342166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135158.

The product of its digits is 1728, while the sum is 25.

The square root of 21342166 is about 4619.7582187816. The cubic root of 21342166 is about 277.3827808903.

Adding to 21342166 its reverse (66124312), we get a palindrome (87466478).

The spelling of 21342166 in words is "twenty-one million, three hundred forty-two thousand, one hundred sixty-six".