73781680 has 80 divisors (see below), whose sum is σ = 197130240. Its totient is φ = 25157376.

The previous prime is 73781651. The next prime is 73781699. The reversal of 73781680 is 8618737.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200857 + ... + 201223.

It is an arithmetic number, because the mean of its divisors is an integer number (2464128).

Almost surely, 2^73781680 is an apocalyptic number.

73781680 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 73781680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98565120).

73781680 is an abundant number, since it is smaller than the sum of its proper divisors (123348560).

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

73781680 is a wasteful number, since it uses less digits than its factorization.

73781680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 746 (or 740 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 73781680 is about 8589.6263015337. The cubic root of 73781680 is about 419.4203644430.

The spelling of 73781680 in words is "seventy-three million, seven hundred eighty-one thousand, six hundred eighty".