641722 has 4 divisors (see below), whose sum is σ = 962586. Its totient is φ = 320860.

The previous prime is 641713. The next prime is 641747. The reversal of 641722 is 227146.

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

It can be written as a sum of positive squares in only one way, i.e., 641601 + 121 = 801^2 + 11^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 641693 and 641702.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160429 + ... + 160432.

2⁶⁴¹⁷²² is an apocalyptic number.

641722 is a deficient number, since it is larger than the sum of its proper divisors (320864).

641722 is a wasteful number, since it uses less digits than its factorization.

641722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320863.

The product of its digits is 672, while the sum is 22.

The square root of 641722 is about 801.0755270260. The cubic root of 641722 is about 86.2546087294.

Adding to 641722 its reverse (227146), we get a palindrome (868868).

The spelling of 641722 in words is "six hundred forty-one thousand, seven hundred twenty-two".