4000320521 has 2 divisors, whose sum is σ = 4000320522. Its totient is φ = 4000320520.

The previous prime is 4000320497. The next prime is 4000320557. The reversal of 4000320521 is 1250230004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2186497600 + 1813822921 = 46760^2 + 42589^2 .

It is a cyclic number.

It is not a de Polignac number, because 4000320521 - 2²⁶ = 3933211657 is a prime.

It is a super-2 number, since 2×4000320521² = 32005128541467422882, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 4000320521.

It is not a weakly prime, because it can be changed into another prime (4000320421) 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, 2000160260 + 2000160261.

It is an arithmetic number, because the mean of its divisors is an integer number (2000160261).

Almost surely, 2^4000320521 is an apocalyptic number.

It is an amenable number.

4000320521 is a deficient number, since it is larger than the sum of its proper divisors (1).

4000320521 is an equidigital number, since it uses as much as digits as its factorization.

4000320521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 4000320521 is about 63248.0870936031. The cubic root of 4000320521 is about 1587.4434504501.

Adding to 4000320521 its reverse (1250230004), we get a palindrome (5250550525).

The spelling of 4000320521 in words is "four billion, three hundred twenty thousand, five hundred twenty-one".