82909440 has 144 divisors (see below), whose sum is σ = 294336000. Its totient is φ = 22099968.

The previous prime is 82909427. The next prime is 82909441. The reversal of 82909440 is 4490928.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×82909440² = 13747950482227200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 82909395 and 82909404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82909441) 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, 33361 + ... + 35759.

It is an arithmetic number, because the mean of its divisors is an integer number (2044000).

Almost surely, 2^82909440 is an apocalyptic number.

82909440 is a gapful number since it is divisible by the number (80) 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 82909440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147168000).

82909440 is an abundant number, since it is smaller than the sum of its proper divisors (211426560).

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

82909440 is a wasteful number, since it uses less digits than its factorization.

82909440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2429 (or 2409 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 82909440 is about 9105.4620970053. The cubic root of 82909440 is about 436.0483631787.

The spelling of 82909440 in words is "eighty-two million, nine hundred nine thousand, four hundred forty".