643719 has 8 divisors (see below), whose sum is σ = 862960. Its totient is φ = 426816.

The previous prime is 643703. The next prime is 643723. The reversal of 643719 is 917346.

It is a happy number.

643719 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 643719 - 2⁴ = 643703 is a prime.

It is a super-2 number, since 2×643719² = 828748301922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643729) 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, 219 + ... + 1155.

It is an arithmetic number, because the mean of its divisors is an integer number (107870).

2⁶⁴³⁷¹⁹ is an apocalyptic number.

643719 is a deficient number, since it is larger than the sum of its proper divisors (219241).

643719 is a wasteful number, since it uses less digits than its factorization.

643719 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1169.

The product of its digits is 4536, while the sum is 30.

The square root of 643719 is about 802.3210080759. The cubic root of 643719 is about 86.3439891175.

The spelling of 643719 in words is "six hundred forty-three thousand, seven hundred nineteen".