67128081 has 4 divisors (see below), whose sum is σ = 89504112. Its totient is φ = 44752052.

The previous prime is 67128077. The next prime is 67128091. The reversal of 67128081 is 18082176.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 67128081 - 2² = 67128077 is a prime.

It is a super-2 number, since 2×67128081² = 9012358517485122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (67128001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11188011 + ... + 11188016.

It is an arithmetic number, because the mean of its divisors is an integer number (22376028).

Almost surely, 2^67128081 is an apocalyptic number.

It is an amenable number.

67128081 is a deficient number, since it is larger than the sum of its proper divisors (22376031).

67128081 is a wasteful number, since it uses less digits than its factorization.

67128081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22376030.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 67128081 is about 8193.1728286421. The cubic root of 67128081 is about 406.4134548247.

The spelling of 67128081 in words is "sixty-seven million, one hundred twenty-eight thousand, eighty-one".