821487361 has 2 divisors, whose sum is σ = 821487362. Its totient is φ = 821487360.

The previous prime is 821487319. The next prime is 821487377. The reversal of 821487361 is 163784128.

821487361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 803382336 + 18105025 = 28344^2 + 4255^2 .

It is a cyclic number.

It is not a de Polignac number, because 821487361 - 2⁹ = 821486849 is a prime.

It is not a weakly prime, because it can be changed into another prime (821487391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410743680 + 410743681.

It is an arithmetic number, because the mean of its divisors is an integer number (410743681).

Almost surely, 2^821487361 is an apocalyptic number.

It is an amenable number.

821487361 is a deficient number, since it is larger than the sum of its proper divisors (1).

821487361 is an equidigital number, since it uses as much as digits as its factorization.

821487361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 40.

The square root of 821487361 is about 28661.6008101432. The cubic root of 821487361 is about 936.5557372688. Note that the first 3 decimals are identical.

The spelling of 821487361 in words is "eight hundred twenty-one million, four hundred eighty-seven thousand, three hundred sixty-one".