999688429 has 2 divisors, whose sum is σ = 999688430. Its totient is φ = 999688428.

The previous prime is 999688427. The next prime is 999688447. The reversal of 999688429 is 924886999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 904625929 + 95062500 = 30077^2 + 9750^2 .

It is an emirp because it is prime and its reverse (924886999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 999688429 - 2¹ = 999688427 is a prime.

Together with 999688427, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999688427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499844214 + 499844215.

It is an arithmetic number, because the mean of its divisors is an integer number (499844215).

Almost surely, 2^999688429 is an apocalyptic number.

It is an amenable number.

999688429 is a deficient number, since it is larger than the sum of its proper divisors (1).

999688429 is an equidigital number, since it uses as much as digits as its factorization.

999688429 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20155392, while the sum is 64.

The square root of 999688429 is about 31617.8498478312. The cubic root of 999688429 is about 999.8961322119.

The spelling of 999688429 in words is "nine hundred ninety-nine million, six hundred eighty-eight thousand, four hundred twenty-nine".