164320421 has 2 divisors, whose sum is σ = 164320422. Its totient is φ = 164320420.

The previous prime is 164320411. The next prime is 164320451. The reversal of 164320421 is 124023461.

164320421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124768900 + 39551521 = 11170^2 + 6289^2 .

It is a cyclic number.

It is not a de Polignac number, because 164320421 - 2⁶ = 164320357 is a prime.

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 (164320411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82160210 + 82160211.

It is an arithmetic number, because the mean of its divisors is an integer number (82160211).

Almost surely, 2^164320421 is an apocalyptic number.

It is an amenable number.

164320421 is a deficient number, since it is larger than the sum of its proper divisors (1).

164320421 is an equidigital number, since it uses as much as digits as its factorization.

164320421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 164320421 is about 12818.7527084346. The cubic root of 164320421 is about 547.7266171956.

Adding to 164320421 its reverse (124023461), we get a palindrome (288343882).

The spelling of 164320421 in words is "one hundred sixty-four million, three hundred twenty thousand, four hundred twenty-one".