643477540 has 48 divisors (see below), whose sum is σ = 1476969984. Its totient is φ = 234432000.

The previous prime is 643477529. The next prime is 643477559. The reversal of 643477540 is 45774346.

It is a junction number, because it is equal to n+sod(n) for n = 643477493 and 643477502.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19986 + ... + 41065.

It is an arithmetic number, because the mean of its divisors is an integer number (30770208).

Almost surely, 2^643477540 is an apocalyptic number.

It is an amenable number.

643477540 is an abundant number, since it is smaller than the sum of its proper divisors (833492444).

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

643477540 is a wasteful number, since it uses less digits than its factorization.

643477540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61108 (or 61106 counting only the distinct ones).

The product of its (nonzero) digits is 282240, while the sum is 40.

The square root of 643477540 is about 25366.8590881883. The cubic root of 643477540 is about 863.3319184578.

The spelling of 643477540 in words is "six hundred forty-three million, four hundred seventy-seven thousand, five hundred forty".