531350021 has 2 divisors, whose sum is σ = 531350022. Its totient is φ = 531350020.

The previous prime is 531350009. The next prime is 531350033. The reversal of 531350021 is 120053135.

It is a balanced prime because it is at equal distance from previous prime (531350009) and next prime (531350033).

It can be written as a sum of positive squares in only one way, i.e., 481802500 + 49547521 = 21950^2 + 7039^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-531350021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 531349975 and 531350002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (531350221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265675010 + 265675011.

It is an arithmetic number, because the mean of its divisors is an integer number (265675011).

Almost surely, 2^531350021 is an apocalyptic number.

It is an amenable number.

531350021 is a deficient number, since it is larger than the sum of its proper divisors (1).

531350021 is an equidigital number, since it uses as much as digits as its factorization.

531350021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 531350021 is about 23051.0308012462. The cubic root of 531350021 is about 809.9537752415.

The spelling of 531350021 in words is "five hundred thirty-one million, three hundred fifty thousand, twenty-one".