641851447 has 4 divisors (see below), whose sum is σ = 641966680. Its totient is φ = 641736216.

The previous prime is 641851429. The next prime is 641851481. The reversal of 641851447 is 744158146.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641851447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641851487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48813 + ... + 60550.

It is an arithmetic number, because the mean of its divisors is an integer number (160491670).

Almost surely, 2^641851447 is an apocalyptic number.

641851447 is a deficient number, since it is larger than the sum of its proper divisors (115233).

641851447 is a wasteful number, since it uses less digits than its factorization.

641851447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115232.

The product of its digits is 107520, while the sum is 40.

The square root of 641851447 is about 25334.7872894169. The cubic root of 641851447 is about 862.6040804735.

The spelling of 641851447 in words is "six hundred forty-one million, eight hundred fifty-one thousand, four hundred forty-seven".