820427 has 2 divisors, whose sum is σ = 820428. Its totient is φ = 820426.

The previous prime is 820411. The next prime is 820429. The reversal of 820427 is 724028.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 820427 - 2⁴ = 820411 is a prime.

Together with 820429, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (820429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410213 + 410214.

It is an arithmetic number, because the mean of its divisors is an integer number (410214).

2⁸²⁰⁴²⁷ is an apocalyptic number.

820427 is a deficient number, since it is larger than the sum of its proper divisors (1).

820427 is an equidigital number, since it uses as much as digits as its factorization.

820427 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 896, while the sum is 23.

The square root of 820427 is about 905.7742544365. The cubic root of 820427 is about 93.6152600707.

The spelling of 820427 in words is "eight hundred twenty thousand, four hundred twenty-seven".