125643 has 16 divisors (see below), whose sum is σ = 198656. Its totient is φ = 69120.

The previous prime is 125641. The next prime is 125651. The reversal of 125643 is 346521.

It is a happy number.

It is not a de Polignac number, because 125643 - 2¹ = 125641 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a d-powerful number, because it can be written as 1 + 2⁷ + 6⁶ + 5⁷ + 4 + 3⁶ .

It is a Duffinian number.

125643 is a lucky number.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125641) 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, 555 + ... + 747.

It is an arithmetic number, because the mean of its divisors is an integer number (12416).

2¹²⁵⁶⁴³ is an apocalyptic number.

125643 is a deficient number, since it is larger than the sum of its proper divisors (73013).

125643 is a wasteful number, since it uses less digits than its factorization.

125643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234.

The product of its digits is 720, while the sum is 21.

The square root of 125643 is about 354.4615635016. The cubic root of 125643 is about 50.0855867479.

The spelling of 125643 in words is "one hundred twenty-five thousand, six hundred forty-three".