164421 has 6 divisors (see below), whose sum is σ = 237510. Its totient is φ = 109608.

The previous prime is 164419. The next prime is 164429. The reversal of 164421 is 124461.

164421 is a `hidden beast` number, since 1 + 644 + 21 = 666.

164421 is nontrivially palindromic in base 8.

It can be written as a sum of positive squares in only one way, i.e., 152100 + 12321 = 390^2 + 111^2 .

It is not a de Polignac number, because 164421 - 2¹ = 164419 is a prime.

It is a super-3 number, since 3×164421³ = 13335002775571383, which contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 164394 and 164403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164429) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9126 + ... + 9143.

It is an arithmetic number, because the mean of its divisors is an integer number (39585).

2¹⁶⁴⁴²¹ is an apocalyptic number.

It is an amenable number.

164421 is a deficient number, since it is larger than the sum of its proper divisors (73089).

164421 is a wasteful number, since it uses less digits than its factorization.

164421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18275 (or 18272 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 164421 is about 405.4885941676. The cubic root of 164421 is about 54.7838347190.

Adding to 164421 its reverse (124461), we get a palindrome (288882).

It can be divided in two parts, 164 and 421, that added together give a palindrome (585).

The spelling of 164421 in words is "one hundred sixty-four thousand, four hundred twenty-one".