643626715 has 16 divisors (see below), whose sum is σ = 829310400. Its totient is φ = 477783040.

The previous prime is 643626689. The next prime is 643626773. The reversal of 643626715 is 517626346.

It is not a de Polignac number, because 643626715 - 2⁷ = 643626587 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47290 + ... + 59359.

It is an arithmetic number, because the mean of its divisors is an integer number (51831900).

Almost surely, 2^643626715 is an apocalyptic number.

643626715 is a deficient number, since it is larger than the sum of its proper divisors (185683685).

643626715 is a wasteful number, since it uses less digits than its factorization.

643626715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106742.

The product of its digits is 181440, while the sum is 40.

The square root of 643626715 is about 25369.7992699982. The cubic root of 643626715 is about 863.3986276435.

The spelling of 643626715 in words is "six hundred forty-three million, six hundred twenty-six thousand, seven hundred fifteen".