78591047 has 2 divisors, whose sum is σ = 78591048. Its totient is φ = 78591046.

The previous prime is 78591043. The next prime is 78591053. The reversal of 78591047 is 74019587.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78591047 - 2² = 78591043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78590995 and 78591013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78591043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39295523 + 39295524.

It is an arithmetic number, because the mean of its divisors is an integer number (39295524).

Almost surely, 2^78591047 is an apocalyptic number.

78591047 is a deficient number, since it is larger than the sum of its proper divisors (1).

78591047 is an equidigital number, since it uses as much as digits as its factorization.

78591047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70560, while the sum is 41.

The square root of 78591047 is about 8865.1591638278. The cubic root of 78591047 is about 428.3423597076.

The spelling of 78591047 in words is "seventy-eight million, five hundred ninety-one thousand, forty-seven".