100639440 has 240 divisors, whose sum is σ = 375350976. Its totient is φ = 23961600.

The previous prime is 100639403. The next prime is 100639453. The reversal of 100639440 is 44936001.

It is a tau number, because it is divible by the number of its divisors (240).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 768175 + ... + 768305.

Almost surely, 2^100639440 is an apocalyptic number.

100639440 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 100639440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187675488).

100639440 is an abundant number, since it is smaller than the sum of its proper divisors (274711536).

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

100639440 is a wasteful number, since it uses less digits than its factorization.

100639440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 100639440 is about 10031.9210523209. The cubic root of 100639440 is about 465.1461212651.

It can be divided in two parts, 10063 and 9440, that added together give a triangular number (19503 = T₁₉₇).

The spelling of 100639440 in words is "one hundred million, six hundred thirty-nine thousand, four hundred forty".