67721760 has 144 divisors (see below), whose sum is σ = 233513280. Its totient is φ = 17871360.

The previous prime is 67721749. The next prime is 67721767. The reversal of 67721760 is 6712776.

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 not an unprimeable number, because it can be changed into a prime (67721767) 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, 188461 + ... + 188819.

It is an arithmetic number, because the mean of its divisors is an integer number (1621620).

Almost surely, 2^67721760 is an apocalyptic number.

67721760 is a gapful number since it is divisible by the number (60) 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 67721760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116756640).

67721760 is an abundant number, since it is smaller than the sum of its proper divisors (165791520).

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

67721760 is a wasteful number, since it uses less digits than its factorization.

67721760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 511 (or 500 counting only the distinct ones).

The product of its (nonzero) digits is 24696, while the sum is 36.

The square root of 67721760 is about 8229.3231799462. The cubic root of 67721760 is about 407.6080434151.

The spelling of 67721760 in words is "sixty-seven million, seven hundred twenty-one thousand, seven hundred sixty".