64638189 has 32 divisors (see below), whose sum is σ = 119393280. Its totient is φ = 33577200.

The previous prime is 64638173. The next prime is 64638191. The reversal of 64638189 is 98183646.

64638189 is a `hidden beast` number, since 6 + 4 + 638 + 1 + 8 + 9 = 666.

It is not a de Polignac number, because 64638189 - 2⁴ = 64638173 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64638109) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13467 + ... + 17624.

It is an arithmetic number, because the mean of its divisors is an integer number (3731040).

Almost surely, 2^64638189 is an apocalyptic number.

It is an amenable number.

64638189 is a deficient number, since it is larger than the sum of its proper divisors (54755091).

64638189 is a wasteful number, since it uses less digits than its factorization.

64638189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31118 (or 31112 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 64638189 is about 8039.7878703359. The cubic root of 64638189 is about 401.3251654102.

The spelling of 64638189 in words is "sixty-four million, six hundred thirty-eight thousand, one hundred eighty-nine".