820614391 has 2 divisors, whose sum is σ = 820614392. Its totient is φ = 820614390.

The previous prime is 820614383. The next prime is 820614409. The reversal of 820614391 is 193416028.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 820614391 - 2³ = 820614383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820614341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410307195 + 410307196.

It is an arithmetic number, because the mean of its divisors is an integer number (410307196).

Almost surely, 2^820614391 is an apocalyptic number.

820614391 is a deficient number, since it is larger than the sum of its proper divisors (1).

820614391 is an equidigital number, since it uses as much as digits as its factorization.

820614391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 820614391 is about 28646.3678500434. The cubic root of 820614391 is about 936.2238697808.

The spelling of 820614391 in words is "eight hundred twenty million, six hundred fourteen thousand, three hundred ninety-one".