100809520 has 80 divisors (see below), whose sum is σ = 276553728. Its totient is φ = 33442560.

The previous prime is 100809517. The next prime is 100809521. The reversal of 100809520 is 25908001.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (100809521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14457 + ... + 20263.

Almost surely, 2^100809520 is an apocalyptic number.

100809520 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 100809520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138276864).

100809520 is an abundant number, since it is smaller than the sum of its proper divisors (175744208).

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

100809520 is a wasteful number, since it uses less digits than its factorization.

100809520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5858 (or 5852 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 100809520 is about 10040.3944145636. The cubic root of 100809520 is about 465.4080051012.

It can be divided in two parts, 10080 and 9520, that added together give a square (19600 = 140²).

The spelling of 100809520 in words is "one hundred million, eight hundred nine thousand, five hundred twenty".