73844640 has 144 divisors (see below), whose sum is σ = 265356000. Its totient is φ = 18648576.

The previous prime is 73844633. The next prime is 73844647. The reversal of 73844640 is 4644837.

73844640 is a `hidden beast` number, since 7 + 3 + 8 + 4 + 4 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (73844633) and next prime (73844647).

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

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 = 73844595 and 73844604.

It is not an unprimeable number, because it can be changed into a prime (73844647) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26011 + ... + 28709.

It is an arithmetic number, because the mean of its divisors is an integer number (1842750).

Almost surely, 2^73844640 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 73844640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132678000).

73844640 is an abundant number, since it is smaller than the sum of its proper divisors (191511360).

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

73844640 is a wasteful number, since it uses less digits than its factorization.

73844640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2739 (or 2728 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The square root of 73844640 is about 8593.2904058923. The cubic root of 73844640 is about 419.5396316220.

The spelling of 73844640 in words is "seventy-three million, eight hundred forty-four thousand, six hundred forty".