78017923 has 2 divisors, whose sum is σ = 78017924. Its totient is φ = 78017922.

The previous prime is 78017921. The next prime is 78017969. The reversal of 78017923 is 32971087.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78017923 - 2¹ = 78017921 is a prime.

Together with 78017921, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (78017921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39008961 + 39008962.

It is an arithmetic number, because the mean of its divisors is an integer number (39008962).

Almost surely, 2^78017923 is an apocalyptic number.

78017923 is a deficient number, since it is larger than the sum of its proper divisors (1).

78017923 is an equidigital number, since it uses as much as digits as its factorization.

78017923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 78017923 is about 8832.7754981093. The cubic root of 78017923 is about 427.2985916727.

The spelling of 78017923 in words is "seventy-eight million, seventeen thousand, nine hundred twenty-three".