643415 has 4 divisors (see below), whose sum is σ = 772104. Its totient is φ = 514728.

The previous prime is 643403. The next prime is 643421. The reversal of 643415 is 514346.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 643415 - 2¹⁶ = 577879 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64337 + ... + 64346.

It is an arithmetic number, because the mean of its divisors is an integer number (193026).

2⁶⁴³⁴¹⁵ is an apocalyptic number.

643415 is a deficient number, since it is larger than the sum of its proper divisors (128689).

643415 is a wasteful number, since it uses less digits than its factorization.

643415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128688.

The product of its digits is 1440, while the sum is 23.

The square root of 643415 is about 802.1315353482. The cubic root of 643415 is about 86.3303948288.

It can be divided in two parts, 64341 and 5, that added together give a palindrome (64346).

The spelling of 643415 in words is "six hundred forty-three thousand, four hundred fifteen".