64641687 has 16 divisors (see below), whose sum is σ = 94892160. Its totient is φ = 38815200.

The previous prime is 64641677. The next prime is 64641691. The reversal of 64641687 is 78614646.

It is not a de Polignac number, because 64641687 - 2⁷ = 64641559 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64641607) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5389 + ... + 12582.

It is an arithmetic number, because the mean of its divisors is an integer number (5930760).

Almost surely, 2^64641687 is an apocalyptic number.

64641687 is a deficient number, since it is larger than the sum of its proper divisors (30250473).

64641687 is a wasteful number, since it uses less digits than its factorization.

64641687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18094.

The product of its digits is 193536, while the sum is 42.

The square root of 64641687 is about 8040.0054104459. The cubic root of 64641687 is about 401.3324047328.

The spelling of 64641687 in words is "sixty-four million, six hundred forty-one thousand, six hundred eighty-seven".