643695480 has 288 divisors, whose sum is σ = 2327551200. Its totient is φ = 153956352.

The previous prime is 643695469. The next prime is 643695499. The reversal of 643695480 is 84596346.

643695480 is a `hidden beast` number, since 6 + 43 + 69 + 548 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2392786 + ... + 2393054.

It is an arithmetic number, because the mean of its divisors is an integer number (8081775).

Almost surely, 2^643695480 is an apocalyptic number.

643695480 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643695480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1163775600).

643695480 is an abundant number, since it is smaller than the sum of its proper divisors (1683855720).

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

643695480 is a wasteful number, since it uses less digits than its factorization.

643695480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The square root of 643695480 is about 25371.1544869365. The cubic root of 643695480 is about 863.4293750166.

The spelling of 643695480 in words is "six hundred forty-three million, six hundred ninety-five thousand, four hundred eighty".