1006664521 has 2 divisors, whose sum is σ = 1006664522. Its totient is φ = 1006664520.

The previous prime is 1006664509. The next prime is 1006664543. The reversal of 1006664521 is 1254666001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 994519296 + 12145225 = 31536^2 + 3485^2 .

It is a cyclic number.

It is not a de Polignac number, because 1006664521 - 2⁵ = 1006664489 is a prime.

It is a super-3 number, since 3×1006664521³ (a number of 28 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (1006664591) 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, 503332260 + 503332261.

It is an arithmetic number, because the mean of its divisors is an integer number (503332261).

Almost surely, 2^1006664521 is an apocalyptic number.

It is an amenable number.

1006664521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1006664521 is an equidigital number, since it uses as much as digits as its factorization.

1006664521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 1006664521 is about 31727.9769446462. The cubic root of 1006664521 is about 1002.2165900981.

The spelling of 1006664521 in words is "one billion, six million, six hundred sixty-four thousand, five hundred twenty-one".