653943 has 4 divisors (see below), whose sum is σ = 871928. Its totient is φ = 435960.

The previous prime is 653941. The next prime is 653951. The reversal of 653943 is 349356.

It is a happy number.

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

It is not a de Polignac number, because 653943 - 2¹ = 653941 is a prime.

It is a D-number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 653943.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (653941) 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, 108988 + ... + 108993.

It is an arithmetic number, because the mean of its divisors is an integer number (217982).

2⁶⁵³⁹⁴³ is an apocalyptic number.

653943 is a deficient number, since it is larger than the sum of its proper divisors (217985).

653943 is a wasteful number, since it uses less digits than its factorization.

653943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217984.

The product of its digits is 9720, while the sum is 30.

The square root of 653943 is about 808.6674223684. The cubic root of 653943 is about 86.7987155338.

It can be divided in two parts, 653 and 943, that added together give a triangular number (1596 = T₅₆).

The spelling of 653943 in words is "six hundred fifty-three thousand, nine hundred forty-three".