643244497 has 8 divisors (see below), whose sum is σ = 739199552. Its totient is φ = 548305200.

The previous prime is 643244479. The next prime is 643244507. The reversal of 643244497 is 794442346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643244497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643244467) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252579 + ... + 255112.

It is an arithmetic number, because the mean of its divisors is an integer number (92399944).

Almost surely, 2^643244497 is an apocalyptic number.

It is an amenable number.

643244497 is a deficient number, since it is larger than the sum of its proper divisors (95955055).

643244497 is a wasteful number, since it uses less digits than its factorization.

643244497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507879.

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

The square root of 643244497 is about 25362.2652182332. The cubic root of 643244497 is about 863.2276839192.

The spelling of 643244497 in words is "six hundred forty-three million, two hundred forty-four thousand, four hundred ninety-seven".