643368427 has 4 divisors (see below), whose sum is σ = 692858320. Its totient is φ = 593878536.

The previous prime is 643368421. The next prime is 643368437. The reversal of 643368427 is 724863346.

It is a happy number.

643368427 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 is a cyclic number.

It is not a de Polignac number, because 643368427 - 2³ = 643368419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643368421) 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, 24744927 + ... + 24744952.

It is an arithmetic number, because the mean of its divisors is an integer number (173214580).

Almost surely, 2^643368427 is an apocalyptic number.

643368427 is a deficient number, since it is larger than the sum of its proper divisors (49489893).

643368427 is a wasteful number, since it uses less digits than its factorization.

643368427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49489892.

The product of its digits is 580608, while the sum is 43.

The square root of 643368427 is about 25364.7082971597. The cubic root of 643368427 is about 863.2831179663.

The spelling of 643368427 in words is "six hundred forty-three million, three hundred sixty-eight thousand, four hundred twenty-seven".