641847 has 4 divisors (see below), whose sum is σ = 855800. Its totient is φ = 427896.

The previous prime is 641843. The next prime is 641863. The reversal of 641847 is 748146.

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

It is not a de Polignac number, because 641847 - 2² = 641843 is a prime.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 641847.

It is not an unprimeable number, because it can be changed into a prime (641843) 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, 106972 + ... + 106977.

It is an arithmetic number, because the mean of its divisors is an integer number (213950).

2⁶⁴¹⁸⁴⁷ is an apocalyptic number.

641847 is a deficient number, since it is larger than the sum of its proper divisors (213953).

641847 is a wasteful number, since it uses less digits than its factorization.

641847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213952.

The product of its digits is 5376, while the sum is 30.

The square root of 641847 is about 801.1535433361. The cubic root of 641847 is about 86.2602088315.

The spelling of 641847 in words is "six hundred forty-one thousand, eight hundred forty-seven".