67940921 has 2 divisors, whose sum is σ = 67940922. Its totient is φ = 67940920.

The previous prime is 67940893. The next prime is 67940927. The reversal of 67940921 is 12904976.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63425296 + 4515625 = 7964^2 + 2125^2 .

It is a cyclic number.

It is not a de Polignac number, because 67940921 - 2¹⁰ = 67939897 is a prime.

It is not a weakly prime, because it can be changed into another prime (67940927) 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 as a sum of consecutive naturals, namely, 33970460 + 33970461.

It is an arithmetic number, because the mean of its divisors is an integer number (33970461).

Almost surely, 2^67940921 is an apocalyptic number.

It is an amenable number.

67940921 is a deficient number, since it is larger than the sum of its proper divisors (1).

67940921 is an equidigital number, since it uses as much as digits as its factorization.

67940921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 67940921 is about 8242.6282822896. The cubic root of 67940921 is about 408.0472700102.

The spelling of 67940921 in words is "sixty-seven million, nine hundred forty thousand, nine hundred twenty-one".