67616021 has 32 divisors (see below), whose sum is σ = 82944000. Its totient is φ = 54362880.

The previous prime is 67615979. The next prime is 67616039. The reversal of 67616021 is 12061676.

It is not a de Polignac number, because 67616021 - 2⁶ = 67615957 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 (67616071) 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 in 31 ways as a sum of consecutive naturals, for example, 339680 + ... + 339878.

It is an arithmetic number, because the mean of its divisors is an integer number (2592000).

Almost surely, 2^67616021 is an apocalyptic number.

It is an amenable number.

67616021 is a deficient number, since it is larger than the sum of its proper divisors (15327979).

67616021 is a wasteful number, since it uses less digits than its factorization.

67616021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 67616021 is about 8222.8961443034. The cubic root of 67616021 is about 407.3957900312.

Adding to 67616021 its reverse (12061676), we get a palindrome (79677697).

The spelling of 67616021 in words is "sixty-seven million, six hundred sixteen thousand, twenty-one".