643542727245345 has 12 divisors (see below), whose sum is σ = 1115474060558676. Its totient is φ = 343222787864160.

The previous prime is 643542727245337. The next prime is 643542727245349. The reversal of 643542727245345 is 543542727245346.

643542727245345 is a `hidden beast` number, since 6 + 4 + 3 + 5 + 4 + 2 + 72 + 7 + 24 + 534 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 198812707209216 + 444730020036129 = 14100096^2 + 21088623^2 .

It is not a de Polignac number, because 643542727245345 - 2³ = 643542727245337 is a prime.

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (643542727245349) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7150474747126 + ... + 7150474747215.

It is an arithmetic number, because the mean of its divisors is an integer number (92956171713223).

Almost surely, 2^{643542727245345} is an apocalyptic number.

It is an amenable number.

643542727245345 is a deficient number, since it is larger than the sum of its proper divisors (471931333313331).

643542727245345 is a wasteful number, since it uses less digits than its factorization.

643542727245345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14300949494352 (or 14300949494349 counting only the distinct ones).

The product of its digits is 677376000, while the sum is 63.

Subtracting from 643542727245345 its reverse (543542727245346), we obtain a palindrome (99999999999999).

The spelling of 643542727245345 in words is "six hundred forty-three trillion, five hundred forty-two billion, seven hundred twenty-seven million, two hundred forty-five thousand, three hundred forty-five".