78606091 has 2 divisors, whose sum is σ = 78606092. Its totient is φ = 78606090.

The previous prime is 78606089. The next prime is 78606103. The reversal of 78606091 is 19060687.

It is a weak prime.

It is an emirp because it is prime and its reverse (19060687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78606091 - 2¹ = 78606089 is a prime.

Together with 78606089, it forms a pair of twin primes.

It is equal to p_4592809 and since 78606091 and 4592809 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78606091.

It is not a weakly prime, because it can be changed into another prime (78606071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39303045 + 39303046.

It is an arithmetic number, because the mean of its divisors is an integer number (39303046).

Almost surely, 2^78606091 is an apocalyptic number.

78606091 is a deficient number, since it is larger than the sum of its proper divisors (1).

78606091 is an equidigital number, since it uses as much as digits as its factorization.

78606091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 78606091 is about 8866.0076133511. The cubic root of 78606091 is about 428.3696892469.

The spelling of 78606091 in words is "seventy-eight million, six hundred six thousand, ninety-one".