643475741 has 4 divisors (see below), whose sum is σ = 643566492. Its totient is φ = 643384992.

The previous prime is 643475699. The next prime is 643475797. The reversal of 643475741 is 147574346.

643475741 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 568584025 + 74891716 = 23845^2 + 8654^2 .

It is a cyclic number.

It is not a de Polignac number, because 643475741 - 2²⁶ = 576366877 is a prime.

It is a super-2 number, since 2×643475741² = 828122058510998162, 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 (643477741) 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, 33746 + ... + 49251.

It is an arithmetic number, because the mean of its divisors is an integer number (160891623).

Almost surely, 2^643475741 is an apocalyptic number.

It is an amenable number.

643475741 is a deficient number, since it is larger than the sum of its proper divisors (90751).

643475741 is an equidigital number, since it uses as much as digits as its factorization.

643475741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90750.

The product of its digits is 282240, while the sum is 41.

The square root of 643475741 is about 25366.8236285113. The cubic root of 643475741 is about 863.3311139047.

The spelling of 643475741 in words is "six hundred forty-three million, four hundred seventy-five thousand, seven hundred forty-one".