641947 has 4 divisors (see below), whose sum is σ = 656920. Its totient is φ = 626976.

The previous prime is 641929. The next prime is 641959. The reversal of 641947 is 749146.

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

It is a cyclic number.

It is not a de Polignac number, because 641947 - 2⁷ = 641819 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (641747) 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, 7422 + ... + 7507.

It is an arithmetic number, because the mean of its divisors is an integer number (164230).

2⁶⁴¹⁹⁴⁷ is an apocalyptic number.

641947 is a deficient number, since it is larger than the sum of its proper divisors (14973).

641947 is a wasteful number, since it uses less digits than its factorization.

641947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14972.

The product of its digits is 6048, while the sum is 31.

The square root of 641947 is about 801.2159509146. The cubic root of 641947 is about 86.2646883897.

The spelling of 641947 in words is "six hundred forty-one thousand, nine hundred forty-seven".