100640 has 48 divisors (see below), whose sum is σ = 258552. Its totient is φ = 36864.

The previous prime is 100621. The next prime is 100649. The reversal of 100640 is 46001.

It can be written as a sum of positive squares in 4 ways, for example, as 99856 + 784 = 316^2 + 28^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2702 + ... + 2738.

2¹⁰⁰⁶⁴⁰ is an apocalyptic number.

100640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 100640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129276).

100640 is an abundant number, since it is smaller than the sum of its proper divisors (157912).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

100640 is a wasteful number, since it uses less digits than its factorization.

100640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 100640 is about 317.2380809424. The cubic root of 100640 is about 46.5146984019.

Adding to 100640 its reverse (46001), we get a palindrome (146641).

It can be divided in two parts, 100 and 640, that multiplied together give a cube (64000 = 40³).

The spelling of 100640 in words is "one hundred thousand, six hundred forty".