643505626334 has 16 divisors (see below), whose sum is σ = 980159917968. Its totient is φ = 316819329792.

The previous prime is 643505626333. The next prime is 643505626349. The reversal of 643505626334 is 433626505346.

It is a super-2 number, since 2×643505626334² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643505626333) 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, 8380664 + ... + 8457099.

It is an arithmetic number, because the mean of its divisors is an integer number (61259994873).

Almost surely, 2^643505626334 is an apocalyptic number.

643505626334 is a deficient number, since it is larger than the sum of its proper divisors (336654291634).

643505626334 is a wasteful number, since it uses less digits than its factorization.

643505626334 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16838059.

The product of its (nonzero) digits is 4665600, while the sum is 47.

The spelling of 643505626334 in words is "six hundred forty-three billion, five hundred five million, six hundred twenty-six thousand, three hundred thirty-four".