18778967 has 2 divisors, whose sum is σ = 18778968. Its totient is φ = 18778966.

The previous prime is 18778957. The next prime is 18778987. The reversal of 18778967 is 76987781.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18778967 - 2⁴ = 18778951 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18778937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9389483 + 9389484.

It is an arithmetic number, because the mean of its divisors is an integer number (9389484).

Almost surely, 2^18778967 is an apocalyptic number.

18778967 is a deficient number, since it is larger than the sum of its proper divisors (1).

18778967 is an equidigital number, since it uses as much as digits as its factorization.

18778967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1185408, while the sum is 53.

The square root of 18778967 is about 4333.4705491096. The cubic root of 18778967 is about 265.8013809293.

The spelling of 18778967 in words is "eighteen million, seven hundred seventy-eight thousand, nine hundred sixty-seven".