20668164 has 24 divisors (see below), whose sum is σ = 52610208. Its totient is φ = 6263040.

The previous prime is 20668157. The next prime is 20668169. The reversal of 20668164 is 46186602.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (20668169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78157 + ... + 78420.

It is an arithmetic number, because the mean of its divisors is an integer number (2192092).

Almost surely, 2^20668164 is an apocalyptic number.

It is an amenable number.

20668164 is an abundant number, since it is smaller than the sum of its proper divisors (31942044).

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

20668164 is a wasteful number, since it uses less digits than its factorization.

20668164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156595 (or 156593 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 20668164 is about 4546.2252473893. The cubic root of 20668164 is about 274.4315043712.

The spelling of 20668164 in words is "twenty million, six hundred sixty-eight thousand, one hundred sixty-four".