99840440 has 128 divisors (see below), whose sum is σ = 276480000.
Its totient is φ = 32344704.
The previous prime is 99840409. The next prime is 99840443. The reversal of 99840440 is 4404899.
It is a super-2 number, since 2×998404402 = 19936226918787200, which contains 22 as substring.
It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.
It is a Harshad number since it is a multiple of its sum of digits (38).
It is a junction number, because it is equal to n+sod(n) for n = 99840394 and 99840403.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (99840443) by changing a digit.
It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 260489 + ... + 260871.
It is an arithmetic number, because the mean of its divisors is an integer number (2160000).
Almost surely, 299840440 is an apocalyptic number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 99840440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138240000).
99840440 is an abundant number, since it is smaller than the sum of its proper divisors (176639560).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
99840440 is a wasteful number, since it uses less digits than its factorization.
99840440 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 434 (or 416 counting only the distinct ones).
The product of its (nonzero) digits is 41472, while the sum is 38.
The square root of 99840440 is about 9992.0188150343.
The cubic root of 99840440 is about 463.9118813044.
The spelling of 99840440 in words is "ninety-nine million, eight hundred forty thousand, four hundred forty".