825786421 has 2 divisors, whose sum is σ = 825786422. Its totient is φ = 825786420.

The previous prime is 825786389. The next prime is 825786427. The reversal of 825786421 is 124687528.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 417180625 + 408605796 = 20425^2 + 20214^2 .

It is a cyclic number.

It is not a de Polignac number, because 825786421 - 2⁵ = 825786389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (825786427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 412893210 + 412893211.

It is an arithmetic number, because the mean of its divisors is an integer number (412893211).

Almost surely, 2^825786421 is an apocalyptic number.

It is an amenable number.

825786421 is a deficient number, since it is larger than the sum of its proper divisors (1).

825786421 is an equidigital number, since it uses as much as digits as its factorization.

825786421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 215040, while the sum is 43.

The square root of 825786421 is about 28736.4998042559. The cubic root of 825786421 is about 938.1866433011.

The spelling of 825786421 in words is "eight hundred twenty-five million, seven hundred eighty-six thousand, four hundred twenty-one".