643745255960 has 16 divisors (see below), whose sum is σ = 1448426826000. Its totient is φ = 257498102368.

The previous prime is 643745255953. The next prime is 643745255971. The reversal of 643745255960 is 69552547346.

It is a junction number, because it is equal to n+sod(n) for n = 643745255896 and 643745255905.

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, 8046815660 + ... + 8046815739.

It is an arithmetic number, because the mean of its divisors is an integer number (90526676625).

Almost surely, 2^643745255960 is an apocalyptic number.

It is an amenable number.

643745255960 is an abundant number, since it is smaller than the sum of its proper divisors (804681570040).

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

643745255960 is a wasteful number, since it uses less digits than its factorization.

643745255960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16093631410 (or 16093631406 counting only the distinct ones).

The product of its (nonzero) digits is 27216000, while the sum is 56.

The spelling of 643745255960 in words is "six hundred forty-three billion, seven hundred forty-five million, two hundred fifty-five thousand, nine hundred sixty".