282021521 has 2 divisors, whose sum is σ = 282021522. Its totient is φ = 282021520.

The previous prime is 282021431. The next prime is 282021527. The reversal of 282021521 is 125120282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 218596225 + 63425296 = 14785^2 + 7964^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-282021521 is a prime.

It is a super-2 number, since 2×282021521² = 159072276614306882, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (282021527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 141010760 + 141010761.

It is an arithmetic number, because the mean of its divisors is an integer number (141010761).

Almost surely, 2^282021521 is an apocalyptic number.

It is an amenable number.

282021521 is a deficient number, since it is larger than the sum of its proper divisors (1).

282021521 is an equidigital number, since it uses as much as digits as its factorization.

282021521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 282021521 is about 16793.4963899719. The cubic root of 282021521 is about 655.7838999495.

The spelling of 282021521 in words is "two hundred eighty-two million, twenty-one thousand, five hundred twenty-one".