64209636 has 18 divisors (see below), whose sum is σ = 162307782. Its totient is φ = 21403200.

The previous prime is 64209623. The next prime is 64209643. The reversal of 64209636 is 63690246.

64209636 is a `hidden beast` number, since 642 + 0 + 9 + 6 + 3 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 63107136 + 1102500 = 7944^2 + 1050^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 1783601 = 64209636 / (6 + 4 + 2 + 0 + 9 + 6 + 3 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 64209636.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 891765 + ... + 891836.

It is an arithmetic number, because the mean of its divisors is an integer number (9017099).

Almost surely, 2^64209636 is an apocalyptic number.

It is an amenable number.

64209636 is an abundant number, since it is smaller than the sum of its proper divisors (98098146).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64209636 is a wasteful number, since it uses less digits than its factorization.

64209636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1783611 (or 1783606 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The square root of 64209636 is about 8013.0915382267. The cubic root of 64209636 is about 400.4362656743.

The spelling of 64209636 in words is "sixty-four million, two hundred nine thousand, six hundred thirty-six".