100445 has 4 divisors (see below), whose sum is σ = 120540. Its totient is φ = 80352.

The previous prime is 100417. The next prime is 100447. The reversal of 100445 is 544001.

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

It can be written as a sum of positive squares in 2 ways, for example, as 23716 + 76729 = 154^2 + 277^2 .

It is a cyclic number.

It is not a de Polignac number, because 100445 - 2⁸ = 100189 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100447) 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, 10040 + ... + 10049.

It is an arithmetic number, because the mean of its divisors is an integer number (30135).

2¹⁰⁰⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

100445 is a deficient number, since it is larger than the sum of its proper divisors (20095).

100445 is an equidigital number, since it uses as much as digits as its factorization.

100445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20094.

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 100445 is about 316.9305917705. The cubic root of 100445 is about 46.4846366944.

Adding to 100445 its reverse (544001), we get a palindrome (644446).

Subtracting 100445 from its reverse (544001), we obtain a square (443556 = 666²).

It can be divided in two parts, 100 and 445, that added together give a palindrome (545).

The spelling of 100445 in words is "one hundred thousand, four hundred forty-five".