831022421 has 2 divisors, whose sum is σ = 831022422. Its totient is φ = 831022420.

The previous prime is 831022417. The next prime is 831022447. The reversal of 831022421 is 124220138.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 632522500 + 198499921 = 25150^2 + 14089^2 .

It is a cyclic number.

It is not a de Polignac number, because 831022421 - 2² = 831022417 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (831024421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 415511210 + 415511211.

It is an arithmetic number, because the mean of its divisors is an integer number (415511211).

Almost surely, 2^831022421 is an apocalyptic number.

It is an amenable number.

831022421 is a deficient number, since it is larger than the sum of its proper divisors (1).

831022421 is an equidigital number, since it uses as much as digits as its factorization.

831022421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 831022421 is about 28827.4594961124. The cubic root of 831022421 is about 940.1653628651.

Adding to 831022421 its reverse (124220138), we get a palindrome (955242559).

The spelling of 831022421 in words is "eight hundred thirty-one million, twenty-two thousand, four hundred twenty-one".