643702245 has 16 divisors (see below), whose sum is σ = 1030659072. Its totient is φ = 343062720.

The previous prime is 643702243. The next prime is 643702249. The reversal of 643702245 is 542207346.

It is not a de Polignac number, because 643702245 - 2¹ = 643702243 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643702243) 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 15 ways as a sum of consecutive naturals, for example, 7479 + ... + 36651.

It is an arithmetic number, because the mean of its divisors is an integer number (64416192).

Almost surely, 2^643702245 is an apocalyptic number.

It is an amenable number.

643702245 is a deficient number, since it is larger than the sum of its proper divisors (386956827).

643702245 is a wasteful number, since it uses less digits than its factorization.

643702245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30652.

The product of its (nonzero) digits is 40320, while the sum is 33.

The square root of 643702245 is about 25371.2878072833. The cubic root of 643702245 is about 863.4323997799.

The spelling of 643702245 in words is "six hundred forty-three million, seven hundred two thousand, two hundred forty-five".