67961921 has 2 divisors, whose sum is σ = 67961922. Its totient is φ = 67961920.

The previous prime is 67961911. The next prime is 67961939. The reversal of 67961921 is 12916976.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66650896 + 1311025 = 8164^2 + 1145^2 .

It is a cyclic number.

It is not a de Polignac number, because 67961921 - 2⁶ = 67961857 is a prime.

It is not a weakly prime, because it can be changed into another prime (67961911) 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 as a sum of consecutive naturals, namely, 33980960 + 33980961.

It is an arithmetic number, because the mean of its divisors is an integer number (33980961).

Almost surely, 2^67961921 is an apocalyptic number.

It is an amenable number.

67961921 is a deficient number, since it is larger than the sum of its proper divisors (1).

67961921 is an equidigital number, since it uses as much as digits as its factorization.

67961921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 41.

The square root of 67961921 is about 8243.9020493938. The cubic root of 67961921 is about 408.0893070713.

The spelling of 67961921 in words is "sixty-seven million, nine hundred sixty-one thousand, nine hundred twenty-one".