64581663 has 8 divisors (see below), whose sum is σ = 86737968. Its totient is φ = 42739904.

The previous prime is 64581653. The next prime is 64581667. The reversal of 64581663 is 36618546.

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 64581663 - 2¹² = 64577567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64581667) 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, 78156 + ... + 78977.

It is an arithmetic number, because the mean of its divisors is an integer number (10842246).

Almost surely, 2^64581663 is an apocalyptic number.

64581663 is a deficient number, since it is larger than the sum of its proper divisors (22156305).

64581663 is a wasteful number, since it uses less digits than its factorization.

64581663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157273.

The product of its digits is 103680, while the sum is 39.

The square root of 64581663 is about 8036.2717101900. The cubic root of 64581663 is about 401.2081452058.

The spelling of 64581663 in words is "sixty-four million, five hundred eighty-one thousand, six hundred sixty-three".