164143561 has 4 divisors (see below), whose sum is σ = 164545300. Its totient is φ = 163741824.

The previous prime is 164143547. The next prime is 164143579. The reversal of 164143561 is 165341461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165341461 = 67 ⋅2467783.

It can be written as a sum of positive squares in 2 ways, for example, as 140280336 + 23863225 = 11844^2 + 4885^2 .

It is a cyclic number.

It is not a de Polignac number, because 164143561 - 2¹³ = 164135369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (164143591) 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, 200256 + ... + 201073.

It is an arithmetic number, because the mean of its divisors is an integer number (41136325).

Almost surely, 2^164143561 is an apocalyptic number.

It is an amenable number.

164143561 is a deficient number, since it is larger than the sum of its proper divisors (401739).

164143561 is an equidigital number, since it uses as much as digits as its factorization.

164143561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401738.

The product of its digits is 8640, while the sum is 31.

The square root of 164143561 is about 12811.8523641197. The cubic root of 164143561 is about 547.5300384539.

The spelling of 164143561 in words is "one hundred sixty-four million, one hundred forty-three thousand, five hundred sixty-one".