643654606416 has 20 divisors (see below), whose sum is σ = 1662774400032. Its totient is φ = 214551535456.

The previous prime is 643654606393. The next prime is 643654606423. The reversal of 643654606416 is 614606456346.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6704735436 + ... + 6704735531.

Almost surely, 2^643654606416 is an apocalyptic number.

It is an amenable number.

643654606416 is an abundant number, since it is smaller than the sum of its proper divisors (1019119793616).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643654606416 is a wasteful number, since it uses less digits than its factorization.

643654606416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13409470978 (or 13409470972 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 51.

The spelling of 643654606416 in words is "six hundred forty-three billion, six hundred fifty-four million, six hundred six thousand, four hundred sixteen".