67778923 has 2 divisors, whose sum is σ = 67778924. Its totient is φ = 67778922.

The previous prime is 67778903. The next prime is 67778933. The reversal of 67778923 is 32987776.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67778923 is a prime.

It is not a weakly prime, because it can be changed into another prime (67778903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33889461 + 33889462.

It is an arithmetic number, because the mean of its divisors is an integer number (33889462).

Almost surely, 2^67778923 is an apocalyptic number.

67778923 is a deficient number, since it is larger than the sum of its proper divisors (1).

67778923 is an equidigital number, since it uses as much as digits as its factorization.

67778923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 889056, while the sum is 49.

The square root of 67778923 is about 8232.7955762305. The cubic root of 67778923 is about 407.7226965974.

The spelling of 67778923 in words is "sixty-seven million, seven hundred seventy-eight thousand, nine hundred twenty-three".