80129909 has 2 divisors, whose sum is σ = 80129910. Its totient is φ = 80129908.

The previous prime is 80129899. The next prime is 80129911. The reversal of 80129909 is 90992108.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78818884 + 1311025 = 8878^2 + 1145^2 .

It is a cyclic number.

It is not a de Polignac number, because 80129909 - 2⁴ = 80129893 is a prime.

Together with 80129911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80129939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40064954 + 40064955.

It is an arithmetic number, because the mean of its divisors is an integer number (40064955).

Almost surely, 2^80129909 is an apocalyptic number.

It is an amenable number.

80129909 is a deficient number, since it is larger than the sum of its proper divisors (1).

80129909 is an equidigital number, since it uses as much as digits as its factorization.

80129909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 38.

The square root of 80129909 is about 8951.5310980860. The cubic root of 80129909 is about 431.1200455871.

The spelling of 80129909 in words is "eighty million, one hundred twenty-nine thousand, nine hundred nine".