643474441 has 2 divisors, whose sum is σ = 643474442. Its totient is φ = 643474440.

The previous prime is 643474423. The next prime is 643474453. The reversal of 643474441 is 144474346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 609892416 + 33582025 = 24696^2 + 5795^2 .

It is a cyclic number.

It is not a de Polignac number, because 643474441 - 2¹⁹ = 642950153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 643474441.

It is not a weakly prime, because it can be changed into another prime (643474411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321737220 + 321737221.

It is an arithmetic number, because the mean of its divisors is an integer number (321737221).

Almost surely, 2^643474441 is an apocalyptic number.

It is an amenable number.

643474441 is a deficient number, since it is larger than the sum of its proper divisors (1).

643474441 is an equidigital number, since it uses as much as digits as its factorization.

643474441 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129024, while the sum is 37.

The square root of 643474441 is about 25366.7980044782. The cubic root of 643474441 is about 863.3305325146.

The spelling of 643474441 in words is "six hundred forty-three million, four hundred seventy-four thousand, four hundred forty-one".