164003221 has 2 divisors, whose sum is σ = 164003222. Its totient is φ = 164003220.

The previous prime is 164003219. The next prime is 164003243. The reversal of 164003221 is 122300461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 153512100 + 10491121 = 12390^2 + 3239^2 .

It is an emirp because it is prime and its reverse (122300461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 164003221 - 2¹ = 164003219 is a prime.

Together with 164003219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164003291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82001610 + 82001611.

It is an arithmetic number, because the mean of its divisors is an integer number (82001611).

Almost surely, 2^164003221 is an apocalyptic number.

It is an amenable number.

164003221 is a deficient number, since it is larger than the sum of its proper divisors (1).

164003221 is an equidigital number, since it uses as much as digits as its factorization.

164003221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 164003221 is about 12806.3742331700. The cubic root of 164003221 is about 547.3739509522.

Adding to 164003221 its reverse (122300461), we get a palindrome (286303682).

The spelling of 164003221 in words is "one hundred sixty-four million, three thousand, two hundred twenty-one".