20671164 has 72 divisors (see below), whose sum is σ = 56259840. Its totient is φ = 6378912.

The previous prime is 20671163. The next prime is 20671187. The reversal of 20671164 is 46117602.

It is a super-2 number, since 2×20671164² = 854594042229792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20671163) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31827 + ... + 32469.

Almost surely, 2^20671164 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20671164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28129920).

20671164 is an abundant number, since it is smaller than the sum of its proper divisors (35588676).

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

20671164 is a wasteful number, since it uses less digits than its factorization.

20671164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719 (or 714 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 20671164 is about 4546.5551794738. Note that the first 3 decimals coincide. The cubic root of 20671164 is about 274.4447817106. Note that the first 3 decimals are identical.

Adding to 20671164 its reverse (46117602), we get a palindrome (66788766).

The spelling of 20671164 in words is "twenty million, six hundred seventy-one thousand, one hundred sixty-four".