820551377 has 2 divisors, whose sum is σ = 820551378. Its totient is φ = 820551376.

The previous prime is 820551367. The next prime is 820551397. The reversal of 820551377 is 773155028.

It is a happy number.

820551377 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 819734161 + 817216 = 28631^2 + 904^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820551377 is a prime.

It is a super-2 number, since 2×820551377² = 1346609124593192258, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 820551377.

It is not a weakly prime, because it can be changed into another prime (820551367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410275688 + 410275689.

It is an arithmetic number, because the mean of its divisors is an integer number (410275689).

Almost surely, 2^820551377 is an apocalyptic number.

It is an amenable number.

820551377 is a deficient number, since it is larger than the sum of its proper divisors (1).

820551377 is an equidigital number, since it uses as much as digits as its factorization.

820551377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58800, while the sum is 38.

The square root of 820551377 is about 28645.2679687239. The cubic root of 820551377 is about 936.1999053294.

The spelling of 820551377 in words is "eight hundred twenty million, five hundred fifty-one thousand, three hundred seventy-seven".