643474423 has 2 divisors, whose sum is σ = 643474424. Its totient is φ = 643474422.

The previous prime is 643474411. The next prime is 643474441. The reversal of 643474423 is 324474346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643474423 - 2⁹ = 643473911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643474453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321737211 + 321737212.

It is an arithmetic number, because the mean of its divisors is an integer number (321737212).

Almost surely, 2^643474423 is an apocalyptic number.

643474423 is a deficient number, since it is larger than the sum of its proper divisors (1).

643474423 is an equidigital number, since it uses as much as digits as its factorization.

643474423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 193536, while the sum is 37.

The square root of 643474423 is about 25366.7976496837. The cubic root of 643474423 is about 863.3305244646.

The spelling of 643474423 in words is "six hundred forty-three million, four hundred seventy-four thousand, four hundred twenty-three".