67721189 has 2 divisors, whose sum is σ = 67721190. Its totient is φ = 67721188.

The previous prime is 67721167. The next prime is 67721197. The reversal of 67721189 is 98112776.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51984100 + 15737089 = 7210^2 + 3967^2 .

It is a cyclic number.

It is not a de Polignac number, because 67721189 - 2²⁴ = 50943973 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67721089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33860594 + 33860595.

It is an arithmetic number, because the mean of its divisors is an integer number (33860595).

Almost surely, 2^67721189 is an apocalyptic number.

It is an amenable number.

67721189 is a deficient number, since it is larger than the sum of its proper divisors (1).

67721189 is an equidigital number, since it uses as much as digits as its factorization.

67721189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42336, while the sum is 41.

The square root of 67721189 is about 8229.2884868620. The cubic root of 67721189 is about 407.6068978215.

The spelling of 67721189 in words is "sixty-seven million, seven hundred twenty-one thousand, one hundred eighty-nine".