164221643 has 4 divisors (see below), whose sum is σ = 166066920. Its totient is φ = 162376368.

The previous prime is 164221627. The next prime is 164221667. The reversal of 164221643 is 346122461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 164221643 - 2⁴ = 164221627 is a prime.

It is a super-3 number, since 3×164221643³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (164221543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 922505 + ... + 922682.

It is an arithmetic number, because the mean of its divisors is an integer number (41516730).

Almost surely, 2^164221643 is an apocalyptic number.

164221643 is a deficient number, since it is larger than the sum of its proper divisors (1845277).

164221643 is an equidigital number, since it uses as much as digits as its factorization.

164221643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1845276.

The product of its digits is 6912, while the sum is 29.

The square root of 164221643 is about 12814.8992582853. The cubic root of 164221643 is about 547.6168434902.

The spelling of 164221643 in words is "one hundred sixty-four million, two hundred twenty-one thousand, six hundred forty-three".