643039461 has 12 divisors (see below), whose sum is σ = 931825440. Its totient is φ = 427312680.

The previous prime is 643039459. The next prime is 643039469. The reversal of 643039461 is 164930346.

643039461 is a `hidden beast` number, since 643 + 0 + 3 + 9 + 4 + 6 + 1 = 666.

It is not a de Polignac number, because 643039461 - 2¹ = 643039459 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643039469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112071 + ... + 117668.

It is an arithmetic number, because the mean of its divisors is an integer number (77652120).

Almost surely, 2^643039461 is an apocalyptic number.

It is an amenable number.

643039461 is a deficient number, since it is larger than the sum of its proper divisors (288785979).

643039461 is a wasteful number, since it uses less digits than its factorization.

643039461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230056 (or 230053 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The square root of 643039461 is about 25358.2227492386. Note that the first 3 decimals coincide. The cubic root of 643039461 is about 863.1359554183.

The spelling of 643039461 in words is "six hundred forty-three million, thirty-nine thousand, four hundred sixty-one".