643547023 has 4 divisors (see below), whose sum is σ = 735482320. Its totient is φ = 551611728.

The previous prime is 643546999. The next prime is 643547101. The reversal of 643547023 is 320745346.

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 643547023 - 2⁵ = 643546991 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 643547023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643541023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45967638 + ... + 45967651.

It is an arithmetic number, because the mean of its divisors is an integer number (183870580).

Almost surely, 2^643547023 is an apocalyptic number.

643547023 is a deficient number, since it is larger than the sum of its proper divisors (91935297).

643547023 is an equidigital number, since it uses as much as digits as its factorization.

643547023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91935296.

The product of its (nonzero) digits is 60480, while the sum is 34.

The square root of 643547023 is about 25368.2286137602. The cubic root of 643547023 is about 863.3629916649.

The spelling of 643547023 in words is "six hundred forty-three million, five hundred forty-seven thousand, twenty-three".