643476427 has 12 divisors (see below), whose sum is σ = 724548888. Its totient is φ = 570706400.

The previous prime is 643476419. The next prime is 643476437. The reversal of 643476427 is 724674346.

It is not a de Polignac number, because 643476427 - 2³ = 643476419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643476437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 59893 + ... + 69814.

It is an arithmetic number, because the mean of its divisors is an integer number (60379074).

Almost surely, 2^643476427 is an apocalyptic number.

643476427 is a deficient number, since it is larger than the sum of its proper divisors (81072461).

643476427 is a wasteful number, since it uses less digits than its factorization.

643476427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129770 (or 129759 counting only the distinct ones).

The product of its digits is 677376, while the sum is 43.

The square root of 643476427 is about 25366.8371501060. The cubic root of 643476427 is about 863.3314206994.

The spelling of 643476427 in words is "six hundred forty-three million, four hundred seventy-six thousand, four hundred twenty-seven".