67778393 has 2 divisors, whose sum is σ = 67778394. Its totient is φ = 67778392.

The previous prime is 67778387. The next prime is 67778419. The reversal of 67778393 is 39387776.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67683529 + 94864 = 8227^2 + 308^2 .

It is a cyclic number.

It is not a de Polignac number, because 67778393 - 2¹⁶ = 67712857 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (67778323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33889196 + 33889197.

It is an arithmetic number, because the mean of its divisors is an integer number (33889197).

Almost surely, 2^67778393 is an apocalyptic number.

It is an amenable number.

67778393 is a deficient number, since it is larger than the sum of its proper divisors (1).

67778393 is an equidigital number, since it uses as much as digits as its factorization.

67778393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1333584, while the sum is 50.

The square root of 67778393 is about 8232.7633878304. The cubic root of 67778393 is about 407.7216338600.

The spelling of 67778393 in words is "sixty-seven million, seven hundred seventy-eight thousand, three hundred ninety-three".