164404991 has 2 divisors, whose sum is σ = 164404992. Its totient is φ = 164404990.

The previous prime is 164404963. The next prime is 164405029. The reversal of 164404991 is 199404461.

It is an a-pointer prime, because the next prime (164405029) can be obtained adding 164404991 to its sum of digits (38).

It is a weak prime.

It is an emirp because it is prime and its reverse (199404461) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-164404991 is a prime.

It is a super-3 number, since 3×164404991³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164404921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82202495 + 82202496.

It is an arithmetic number, because the mean of its divisors is an integer number (82202496).

Almost surely, 2^164404991 is an apocalyptic number.

164404991 is a deficient number, since it is larger than the sum of its proper divisors (1).

164404991 is an equidigital number, since it uses as much as digits as its factorization.

164404991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 164404991 is about 12822.0509669865. The cubic root of 164404991 is about 547.8205663537.

The spelling of 164404991 in words is "one hundred sixty-four million, four hundred four thousand, nine hundred ninety-one".