643097207 has 4 divisors (see below), whose sum is σ = 658053000. Its totient is φ = 628141416.

The previous prime is 643097171. The next prime is 643097239. The reversal of 643097207 is 702790346.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643097207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643097107) 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, 7477832 + ... + 7477917.

It is an arithmetic number, because the mean of its divisors is an integer number (164513250).

Almost surely, 2^643097207 is an apocalyptic number.

643097207 is a deficient number, since it is larger than the sum of its proper divisors (14955793).

643097207 is a wasteful number, since it uses less digits than its factorization.

643097207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14955792.

The product of its (nonzero) digits is 63504, while the sum is 38.

The square root of 643097207 is about 25359.3613287086. The cubic root of 643097207 is about 863.1617916538.

The spelling of 643097207 in words is "six hundred forty-three million, ninety-seven thousand, two hundred seven".