67020317921 has 4 divisors (see below), whose sum is σ = 67021229844. Its totient is φ = 67019406000.

The previous prime is 67020317827. The next prime is 67020317927. The reversal of 67020317921 is 12971302076.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24268966225 + 42751351696 = 155785^2 + 206764^2 .

It is a cyclic number.

It is not a de Polignac number, because 67020317921 - 2¹⁰ = 67020316897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67020317927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 335030 + ... + 496271.

It is an arithmetic number, because the mean of its divisors is an integer number (16755307461).

Almost surely, 2^67020317921 is an apocalyptic number.

It is an amenable number.

67020317921 is a deficient number, since it is larger than the sum of its proper divisors (911923).

67020317921 is an equidigital number, since it uses as much as digits as its factorization.

67020317921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911922.

The product of its (nonzero) digits is 31752, while the sum is 38.

Adding to 67020317921 its reverse (12971302076), we get a palindrome (79991619997).

The spelling of 67020317921 in words is "sixty-seven billion, twenty million, three hundred seventeen thousand, nine hundred twenty-one".