166564565 has 8 divisors (see below), whose sum is σ = 205279800. Its totient is φ = 129650112.

The previous prime is 166564561. The next prime is 166564571. The reversal of 166564565 is 565465661.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 21169201 + 145395364 = 4601^2 + 12058^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 166564565 - 2² = 166564561 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166564561) 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, 449990 + ... + 450359.

It is an arithmetic number, because the mean of its divisors is an integer number (25659975).

Almost surely, 2^166564565 is an apocalyptic number.

It is an amenable number.

166564565 is a deficient number, since it is larger than the sum of its proper divisors (38715235).

166564565 is an equidigital number, since it uses as much as digits as its factorization.

166564565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 900391.

The product of its digits is 648000, while the sum is 44.

The square root of 166564565 is about 12905.9895010030. The cubic root of 166564565 is about 550.2088077683.

The spelling of 166564565 in words is "one hundred sixty-six million, five hundred sixty-four thousand, five hundred sixty-five".