9999809929 has 2 divisors, whose sum is σ = 9999809930. Its totient is φ = 9999809928.

The previous prime is 9999809893. The next prime is 9999809959. The reversal of 9999809929 is 9299089999.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9954651529 + 45158400 = 99773^2 + 6720^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9999809929 is a prime.

It is a super-2 number, since 2×9999809929² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9999809959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999904964 + 4999904965.

It is an arithmetic number, because the mean of its divisors is an integer number (4999904965).

Almost surely, 2^9999809929 is an apocalyptic number.

It is an amenable number.

9999809929 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999809929 is an equidigital number, since it uses as much as digits as its factorization.

9999809929 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 76527504, while the sum is 73.

The square root of 9999809929 is about 99999.0496404841. The cubic root of 9999809929 is about 2154.4210400935.

The spelling of 9999809929 in words is "nine billion, nine hundred ninety-nine million, eight hundred nine thousand, nine hundred twenty-nine".