643772406516 has 96 divisors (see below), whose sum is σ = 1532332032000. Its totient is φ = 210319694208.

The previous prime is 643772406481. The next prime is 643772406601. The reversal of 643772406516 is 615604277346.

It is a super-2 number, since 2×643772406516² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 261801295 + ... + 261803753.

It is an arithmetic number, because the mean of its divisors is an integer number (15961792000).

Almost surely, 2^643772406516 is an apocalyptic number.

It is an amenable number.

643772406516 is an abundant number, since it is smaller than the sum of its proper divisors (888559625484).

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

643772406516 is a wasteful number, since it uses less digits than its factorization.

643772406516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4461 (or 4459 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 51.

The spelling of 643772406516 in words is "six hundred forty-three billion, seven hundred seventy-two million, four hundred six thousand, five hundred sixteen".