67866721 has 16 divisors (see below), whose sum is σ = 76599936. Its totient is φ = 59659776.

The previous prime is 67866707. The next prime is 67866751. The reversal of 67866721 is 12766876.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67866721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (67866751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 105226 + ... + 105868.

It is an arithmetic number, because the mean of its divisors is an integer number (4787496).

Almost surely, 2^67866721 is an apocalyptic number.

It is an amenable number.

67866721 is a deficient number, since it is larger than the sum of its proper divisors (8733215).

67866721 is a wasteful number, since it uses less digits than its factorization.

67866721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1032.

The product of its digits is 169344, while the sum is 43.

The square root of 67866721 is about 8238.1260611865. The cubic root of 67866721 is about 407.8986696487.

The spelling of 67866721 in words is "sixty-seven million, eight hundred sixty-six thousand, seven hundred twenty-one".