643551453634 has 16 divisors (see below), whose sum is σ = 973260852480. Its totient is φ = 319141898640.

The previous prime is 643551453619. The next prime is 643551453689. The reversal of 643551453634 is 436354155346.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2562072 + ... + 2802019.

It is an arithmetic number, because the mean of its divisors is an integer number (60828803280).

Almost surely, 2^643551453634 is an apocalyptic number.

643551453634 is a deficient number, since it is larger than the sum of its proper divisors (329709398846).

643551453634 is a wasteful number, since it uses less digits than its factorization.

643551453634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5364585.

The product of its digits is 7776000, while the sum is 49.

The spelling of 643551453634 in words is "six hundred forty-three billion, five hundred fifty-one million, four hundred fifty-three thousand, six hundred thirty-four".