611643 has 16 divisors (see below), whose sum is σ = 881280. Its totient is φ = 375936.

The previous prime is 611641. The next prime is 611657. The reversal of 611643 is 346116.

It is not a de Polignac number, because 611643 - 2¹ = 611641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (611641) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 3328 + ... + 3506.

It is an arithmetic number, because the mean of its divisors is an integer number (55080).

2⁶¹¹⁶⁴³ is an apocalyptic number.

611643 is a deficient number, since it is larger than the sum of its proper divisors (269637).

611643 is a wasteful number, since it uses less digits than its factorization.

611643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266.

The product of its digits is 432, while the sum is 21.

The square root of 611643 is about 782.0760832553. The cubic root of 611643 is about 84.8853355841.

Adding to 611643 its reverse (346116), we get a palindrome (957759).

The spelling of 611643 in words is "six hundred eleven thousand, six hundred forty-three".