164435021 has 2 divisors, whose sum is σ = 164435022. Its totient is φ = 164435020.

The previous prime is 164434997. The next prime is 164435057. The reversal of 164435021 is 120534461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 155500900 + 8934121 = 12470^2 + 2989^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-164435021 is a prime.

It is a super-3 number, since 3×164435021³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164435081) 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 as a sum of consecutive naturals, namely, 82217510 + 82217511.

It is an arithmetic number, because the mean of its divisors is an integer number (82217511).

Almost surely, 2^164435021 is an apocalyptic number.

It is an amenable number.

164435021 is a deficient number, since it is larger than the sum of its proper divisors (1).

164435021 is an equidigital number, since it uses as much as digits as its factorization.

164435021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 164435021 is about 12823.2219430220. The cubic root of 164435021 is about 547.8539190517.

Adding to 164435021 its reverse (120534461), we get a palindrome (284969482).

The spelling of 164435021 in words is "one hundred sixty-four million, four hundred thirty-five thousand, twenty-one".