531229021 has 2 divisors, whose sum is σ = 531229022. Its totient is φ = 531229020.

The previous prime is 531229007. The next prime is 531229031. The reversal of 531229021 is 120922135.

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., 530611225 + 617796 = 23035^2 + 786^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-531229021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (531229031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265614510 + 265614511.

It is an arithmetic number, because the mean of its divisors is an integer number (265614511).

Almost surely, 2^531229021 is an apocalyptic number.

It is an amenable number.

531229021 is a deficient number, since it is larger than the sum of its proper divisors (1).

531229021 is an equidigital number, since it uses as much as digits as its factorization.

531229021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 531229021 is about 23048.4060403317. The cubic root of 531229021 is about 809.8922891883.

The spelling of 531229021 in words is "five hundred thirty-one million, two hundred twenty-nine thousand, twenty-one".