73640 has 32 divisors (see below), whose sum is σ = 190080. Its totient is φ = 25152.

The previous prime is 73637. The next prime is 73643. The reversal of 73640 is 4637.

It is an interprime number because it is at equal distance from previous prime (73637) and next prime (73643).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73643) 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, 149 + ... + 411.

It is an arithmetic number, because the mean of its divisors is an integer number (5940).

2⁷³⁶⁴⁰ is an apocalyptic number.

73640 is a gapful number since it is divisible by the number (70) 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 73640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95040).

73640 is an abundant number, since it is smaller than the sum of its proper divisors (116440).

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

73640 is a wasteful number, since it uses less digits than its factorization.

73640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 73640 is about 271.3669102894. The cubic root of 73640 is about 41.9151727052.

The spelling of 73640 in words is "seventy-three thousand, six hundred forty".