100945 has 8 divisors (see below), whose sum is σ = 130536. Its totient is φ = 74496.

The previous prime is 100943. The next prime is 100957. The reversal of 100945 is 549001.

It can be written as a sum of positive squares in 4 ways, for example, as 1089 + 99856 = 33^2 + 316^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 100945 - 2¹ = 100943 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 712 + ... + 841.

It is an arithmetic number, because the mean of its divisors is an integer number (16317).

2¹⁰⁰⁹⁴⁵ is an apocalyptic number.

It is an amenable number.

100945 is a deficient number, since it is larger than the sum of its proper divisors (29591).

100945 is a wasteful number, since it uses less digits than its factorization.

100945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 100945 is about 317.7184288014. The cubic root of 100945 is about 46.5616402256.

Adding to 100945 its reverse (549001), we get a palindrome (649946).

The spelling of 100945 in words is "one hundred thousand, nine hundred forty-five".