64840143 has 16 divisors (see below), whose sum is σ = 89642880. Its totient is φ = 41639136.

The previous prime is 64840129. The next prime is 64840157. The reversal of 64840143 is 34104846.

It is an interprime number because it is at equal distance from previous prime (64840129) and next prime (64840157).

It is not a de Polignac number, because 64840143 - 2¹⁰ = 64839119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 64840143.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64840123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67996 + ... + 68942.

It is an arithmetic number, because the mean of its divisors is an integer number (5602680).

Almost surely, 2^64840143 is an apocalyptic number.

64840143 is a deficient number, since it is larger than the sum of its proper divisors (24802737).

64840143 is a wasteful number, since it uses less digits than its factorization.

64840143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1766.

The product of its (nonzero) digits is 9216, while the sum is 30.

The square root of 64840143 is about 8052.3377350928. The cubic root of 64840143 is about 401.7426944309.

Adding to 64840143 its reverse (34104846), we get a palindrome (98944989).

The spelling of 64840143 in words is "sixty-four million, eight hundred forty thousand, one hundred forty-three".