6321610661 has 2 divisors, whose sum is σ = 6321610662. Its totient is φ = 6321610660.

The previous prime is 6321610627. The next prime is 6321610709. The reversal of 6321610661 is 1660161236.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5379489025 + 942121636 = 73345^2 + 30694^2 .

It is a cyclic number.

It is not a de Polignac number, because 6321610661 - 2⁶ = 6321610597 is a prime.

It is a super-2 number, since 2×6321610661² = 79925522698537713842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6321610601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3160805330 + 3160805331.

It is an arithmetic number, because the mean of its divisors is an integer number (3160805331).

Almost surely, 2^6321610661 is an apocalyptic number.

It is an amenable number.

6321610661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6321610661 is an equidigital number, since it uses as much as digits as its factorization.

6321610661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 6321610661 is about 79508.5571558181. The cubic root of 6321610661 is about 1849.0241418719.

Adding to 6321610661 its reverse (1660161236), we get a palindrome (7981771897).

The spelling of 6321610661 in words is "six billion, three hundred twenty-one million, six hundred ten thousand, six hundred sixty-one".