821725013 has 2 divisors, whose sum is σ = 821725014. Its totient is φ = 821725012.

The previous prime is 821725007. The next prime is 821725033. The reversal of 821725013 is 310527128.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 677196529 + 144528484 = 26023^2 + 12022^2 .

It is a cyclic number.

It is not a de Polignac number, because 821725013 - 2⁴ = 821724997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821725033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410862506 + 410862507.

It is an arithmetic number, because the mean of its divisors is an integer number (410862507).

Almost surely, 2^821725013 is an apocalyptic number.

It is an amenable number.

821725013 is a deficient number, since it is larger than the sum of its proper divisors (1).

821725013 is an equidigital number, since it uses as much as digits as its factorization.

821725013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3360, while the sum is 29.

The square root of 821725013 is about 28665.7463360018. The cubic root of 821725013 is about 936.6460421210.

The spelling of 821725013 in words is "eight hundred twenty-one million, seven hundred twenty-five thousand, thirteen".