643061533427 has 4 divisors (see below), whose sum is σ = 643698860040. Its totient is φ = 642424206816.

The previous prime is 643061533403. The next prime is 643061533451. The reversal of 643061533427 is 724335160346.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (643061533403) and next prime (643061533451).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643061533427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643061533027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318661793 + ... + 318663810.

It is an arithmetic number, because the mean of its divisors is an integer number (160924715010).

Almost surely, 2^643061533427 is an apocalyptic number.

643061533427 is a deficient number, since it is larger than the sum of its proper divisors (637326613).

643061533427 is a wasteful number, since it uses less digits than its factorization.

643061533427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637326612.

The product of its (nonzero) digits is 1088640, while the sum is 44.

The spelling of 643061533427 in words is "six hundred forty-three billion, sixty-one million, five hundred thirty-three thousand, four hundred twenty-seven".