643546512 has 160 divisors (see below), whose sum is σ = 2147481600. Its totient is φ = 180703872.

The previous prime is 643546507. The next prime is 643546517. The reversal of 643546512 is 215645346.

643546512 is a `hidden beast` number, since 64 + 3 + 546 + 51 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (643546507) and next prime (643546517).

It is a super-2 number, since 2×643546512² = 828304226214732288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (643546517) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 176613 + ... + 180219.

It is an arithmetic number, because the mean of its divisors is an integer number (13421760).

Almost surely, 2^643546512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643546512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1073740800).

643546512 is an abundant number, since it is smaller than the sum of its proper divisors (1503935088).

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

643546512 is a wasteful number, since it uses less digits than its factorization.

643546512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3690 (or 3678 counting only the distinct ones).

The product of its digits is 86400, while the sum is 36.

The square root of 643546512 is about 25368.2185421050. The cubic root of 643546512 is about 863.3627631509.

The spelling of 643546512 in words is "six hundred forty-three million, five hundred forty-six thousand, five hundred twelve".