78387847 has 2 divisors, whose sum is σ = 78387848. Its totient is φ = 78387846.

The previous prime is 78387823. The next prime is 78387889. The reversal of 78387847 is 74878387.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78387847 - 2¹¹ = 78385799 is a prime.

It is a super-2 number, since 2×78387847² = 12289309114590818, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78387794 and 78387803.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78387347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39193923 + 39193924.

It is an arithmetic number, because the mean of its divisors is an integer number (39193924).

Almost surely, 2^78387847 is an apocalyptic number.

78387847 is a deficient number, since it is larger than the sum of its proper divisors (1).

78387847 is an equidigital number, since it uses as much as digits as its factorization.

78387847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2107392, while the sum is 52.

The square root of 78387847 is about 8853.6911511527. The cubic root of 78387847 is about 427.9728761889.

The spelling of 78387847 in words is "seventy-eight million, three hundred eighty-seven thousand, eight hundred forty-seven".