49840 has 40 divisors (see below), whose sum is σ = 133920. Its totient is φ = 16896.

The previous prime is 49831. The next prime is 49843. The reversal of 49840 is 4894.

It is a tau number, because it is divible by the number of its divisors (40).

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (49843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 516 + ... + 604.

It is an arithmetic number, because the mean of its divisors is an integer number (3348).

2⁴⁹⁸⁴⁰ is an apocalyptic number.

49840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

49840 is the 112-nd decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 49840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66960).

49840 is an abundant number, since it is smaller than the sum of its proper divisors (84080).

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

49840 is a wasteful number, since it uses less digits than its factorization.

49840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 49840 is about 223.2487401980. The cubic root of 49840 is about 36.8009766596.

The spelling of 49840 in words is "forty-nine thousand, eight hundred forty".