643531610225506 has 16 divisors (see below), whose sum is σ = 971275506974208. Its totient is φ = 319779029736000.

The previous prime is 643531610225437. The next prime is 643531610225557. The reversal of 643531610225506 is 605522016135346.

It is a self number, because there is not a number n which added to its sum of digits gives 643531610225506.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1480241130 + ... + 1480675813.

It is an arithmetic number, because the mean of its divisors is an integer number (60704719185888).

Almost surely, 2^{643531610225506} is an apocalyptic number.

643531610225506 is a deficient number, since it is larger than the sum of its proper divisors (327743896748702).

643531610225506 is a wasteful number, since it uses less digits than its factorization.

643531610225506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2960917617.

The product of its (nonzero) digits is 3888000, while the sum is 49.

The spelling of 643531610225506 in words is "six hundred forty-three trillion, five hundred thirty-one billion, six hundred ten million, two hundred twenty-five thousand, five hundred six".