999688427 has 2 divisors, whose sum is σ = 999688428. Its totient is φ = 999688426.

The previous prime is 999688387. The next prime is 999688429. The reversal of 999688427 is 724886999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999688427 - 2⁸ = 999688171 is a prime.

Together with 999688429, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 999688427.

It is not a weakly prime, because it can be changed into another prime (999688429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499844213 + 499844214.

It is an arithmetic number, because the mean of its divisors is an integer number (499844214).

Almost surely, 2^999688427 is an apocalyptic number.

999688427 is a deficient number, since it is larger than the sum of its proper divisors (1).

999688427 is an equidigital number, since it uses as much as digits as its factorization.

999688427 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15676416, while the sum is 62.

The square root of 999688427 is about 31617.8498162035. The cubic root of 999688427 is about 999.8961315451.

The spelling of 999688427 in words is "nine hundred ninety-nine million, six hundred eighty-eight thousand, four hundred twenty-seven".