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64220161 = 159740213

64220161 has 4 divisors (see below), whose sum is σ = 64261972. Its totient is φ = 64178352.

The previous prime is 64220147. The next prime is 64220179. The reversal of 64220161 is 16102246.

64220161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16102246 = 28051123.

It can be written as a sum of positive squares in 2 ways, for example, as 20250000 + 43970161 = 4500^2 + 6631^2 .

It is a cyclic number.

It is not a de Polignac number, because 64220161 - 213 = 64211969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64220131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18510 + ... + 21703.

It is an arithmetic number, because the mean of its divisors is an integer number (16065493).

It is a 1536-hyperperfect number.

Almost surely, 264220161 is an apocalyptic number.

It is an amenable number.

64220161 is a deficient number, since it is larger than the sum of its proper divisors (41811).

64220161 is a wasteful number, since it uses less digits than its factorization.

64220161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41810.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 64220161 is about 8013.7482491029. The cubic root of 64220161 is about 400.4581438103.

The spelling of 64220161 in words is "sixty-four million, two hundred twenty thousand, one hundred sixty-one".

Divisors: 1 1597 40213 64220161