18078947 has 2 divisors, whose sum is σ = 18078948. Its totient is φ = 18078946.

The previous prime is 18078911. The next prime is 18079031. The reversal of 18078947 is 74987081.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18078947 - 2²² = 13884643 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18078898 and 18078907.

It is not a weakly prime, because it can be changed into another prime (18078547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9039473 + 9039474.

It is an arithmetic number, because the mean of its divisors is an integer number (9039474).

Almost surely, 2^18078947 is an apocalyptic number.

18078947 is a deficient number, since it is larger than the sum of its proper divisors (1).

18078947 is an equidigital number, since it uses as much as digits as its factorization.

18078947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112896, while the sum is 44.

The square root of 18078947 is about 4251.9345009066. The cubic root of 18078947 is about 262.4567281658.

The spelling of 18078947 in words is "eighteen million, seventy-eight thousand, nine hundred forty-seven".