164205561 has 8 divisors (see below), whose sum is σ = 235782400. Its totient is φ = 101049552.

The previous prime is 164205551. The next prime is 164205563. The reversal of 164205561 is 165502461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 164205561 - 2¹⁵ = 164172793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (164205563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2105161 + ... + 2105238.

It is an arithmetic number, because the mean of its divisors is an integer number (29472800).

Almost surely, 2^164205561 is an apocalyptic number.

It is an amenable number.

164205561 is a deficient number, since it is larger than the sum of its proper divisors (71576839).

164205561 is a wasteful number, since it uses less digits than its factorization.

164205561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4210415.

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 164205561 is about 12814.2717701787. The cubic root of 164205561 is about 547.5989671181.

The spelling of 164205561 in words is "one hundred sixty-four million, two hundred five thousand, five hundred sixty-one".