67721616 has 80 divisors (see below), whose sum is σ = 197755200. Its totient is φ = 22182912.

The previous prime is 67721597. The next prime is 67721653. The reversal of 67721616 is 61612776.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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, 24160 + ... + 26816.

It is an arithmetic number, because the mean of its divisors is an integer number (2471940).

Almost surely, 2^67721616 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 67721616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98877600).

67721616 is an abundant number, since it is smaller than the sum of its proper divisors (130033584).

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

67721616 is a wasteful number, since it uses less digits than its factorization.

67721616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2733 (or 2721 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 67721616 is about 8229.3144307409. The cubic root of 67721616 is about 407.6077545094.

The spelling of 67721616 in words is "sixty-seven million, seven hundred twenty-one thousand, six hundred sixteen".