78015923 has 2 divisors, whose sum is σ = 78015924. Its totient is φ = 78015922.

The previous prime is 78015913. The next prime is 78015937. The reversal of 78015923 is 32951087.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78015923 - 2⁸ = 78015667 is a prime.

It is not a weakly prime, because it can be changed into another prime (78015913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39007961 + 39007962.

It is an arithmetic number, because the mean of its divisors is an integer number (39007962).

Almost surely, 2^78015923 is an apocalyptic number.

78015923 is a deficient number, since it is larger than the sum of its proper divisors (1).

78015923 is an equidigital number, since it uses as much as digits as its factorization.

78015923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 78015923 is about 8832.6622826869. The cubic root of 78015923 is about 427.2949403558.

The spelling of 78015923 in words is "seventy-eight million, fifteen thousand, nine hundred twenty-three".