67140821 has 12 divisors (see below), whose sum is σ = 75095232. Its totient is φ = 59532000.

The previous prime is 67140817. The next prime is 67140869. The reversal of 67140821 is 12804176.

It is not a de Polignac number, because 67140821 - 2² = 67140817 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67140811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16676 + ... + 20306.

It is an arithmetic number, because the mean of its divisors is an integer number (6257936).

Almost surely, 2^67140821 is an apocalyptic number.

It is an amenable number.

67140821 is a deficient number, since it is larger than the sum of its proper divisors (7954411).

67140821 is a wasteful number, since it uses less digits than its factorization.

67140821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3724 (or 3683 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 67140821 is about 8193.9502683382. The cubic root of 67140821 is about 406.4391637869.

Adding to 67140821 its reverse (12804176), we get a palindrome (79944997).

The spelling of 67140821 in words is "sixty-seven million, one hundred forty thousand, eight hundred twenty-one".