643475541 has 4 divisors (see below), whose sum is σ = 857967392. Its totient is φ = 428983692.

The previous prime is 643475533. The next prime is 643475563. The reversal of 643475541 is 145574346.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 643475541 - 2³ = 643475533 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 643475541.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643405541) 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, 107245921 + ... + 107245926.

It is an arithmetic number, because the mean of its divisors is an integer number (214491848).

Almost surely, 2^643475541 is an apocalyptic number.

It is an amenable number.

643475541 is a deficient number, since it is larger than the sum of its proper divisors (214491851).

643475541 is a wasteful number, since it uses less digits than its factorization.

643475541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214491850.

The product of its digits is 201600, while the sum is 39.

The square root of 643475541 is about 25366.8196863541. The cubic root of 643475541 is about 863.3310244601.

The spelling of 643475541 in words is "six hundred forty-three million, four hundred seventy-five thousand, five hundred forty-one".