84078091 has 2 divisors, whose sum is σ = 84078092. Its totient is φ = 84078090.

The previous prime is 84078089. The next prime is 84078103. The reversal of 84078091 is 19087048.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 84078091 - 2¹ = 84078089 is a prime.

Together with 84078089, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 84078091.

It is not a weakly prime, because it can be changed into another prime (84078011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42039045 + 42039046.

It is an arithmetic number, because the mean of its divisors is an integer number (42039046).

Almost surely, 2^84078091 is an apocalyptic number.

84078091 is a deficient number, since it is larger than the sum of its proper divisors (1).

84078091 is an equidigital number, since it uses as much as digits as its factorization.

84078091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 84078091 is about 9169.4106135564. The cubic root of 84078091 is about 438.0875866487.

The spelling of 84078091 in words is "eighty-four million, seventy-eight thousand, ninety-one".