67998109 has 2 divisors, whose sum is σ = 67998110. Its totient is φ = 67998108.

The previous prime is 67998083. The next prime is 67998121. The reversal of 67998109 is 90189976.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65367225 + 2630884 = 8085^2 + 1622^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67998109 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 (67998209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33999054 + 33999055.

It is an arithmetic number, because the mean of its divisors is an integer number (33999055).

Almost surely, 2^67998109 is an apocalyptic number.

It is an amenable number.

67998109 is a deficient number, since it is larger than the sum of its proper divisors (1).

67998109 is an equidigital number, since it uses as much as digits as its factorization.

67998109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 244944, while the sum is 49.

The square root of 67998109 is about 8246.0965917214. The cubic root of 67998109 is about 408.1617266224.

The spelling of 67998109 in words is "sixty-seven million, nine hundred ninety-eight thousand, one hundred nine".