821077513 has 2 divisors, whose sum is σ = 821077514. Its totient is φ = 821077512.

The previous prime is 821077427. The next prime is 821077531. The reversal of 821077513 is 315770128.

Together with next prime (821077531) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 807298569 + 13778944 = 28413^2 + 3712^2 .

It is a cyclic number.

It is not a de Polignac number, because 821077513 - 2²⁵ = 787523081 is a prime.

It is not a weakly prime, because it can be changed into another prime (821077553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410538756 + 410538757.

It is an arithmetic number, because the mean of its divisors is an integer number (410538757).

Almost surely, 2^821077513 is an apocalyptic number.

It is an amenable number.

821077513 is a deficient number, since it is larger than the sum of its proper divisors (1).

821077513 is an equidigital number, since it uses as much as digits as its factorization.

821077513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11760, while the sum is 34.

The square root of 821077513 is about 28654.4501430406. The cubic root of 821077513 is about 936.3999591171.

The spelling of 821077513 in words is "eight hundred twenty-one million, seventy-seven thousand, five hundred thirteen".