643622220505 has 48 divisors (see below), whose sum is σ = 864218678400. Its totient is φ = 459682572800.

The previous prime is 643622220491. The next prime is 643622220541. The reversal of 643622220505 is 505022226346.

It is not a de Polignac number, because 643622220505 - 2¹⁷ = 643622089433 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36792801 + ... + 36810289.

It is an arithmetic number, because the mean of its divisors is an integer number (18004555800).

Almost surely, 2^643622220505 is an apocalyptic number.

It is an amenable number.

643622220505 is a deficient number, since it is larger than the sum of its proper divisors (220596457895).

643622220505 is a wasteful number, since it uses less digits than its factorization.

643622220505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18606 (or 18595 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 37.

The spelling of 643622220505 in words is "six hundred forty-three billion, six hundred twenty-two million, two hundred twenty thousand, five hundred five".