10002661 has 2 divisors, whose sum is σ = 10002662. Its totient is φ = 10002660.

The previous prime is 10002659. The next prime is 10002667. The reversal of 10002661 is 16620001.

10002661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8014561 + 1988100 = 2831^2 + 1410^2 .

It is an emirp because it is prime and its reverse (16620001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10002661 - 2¹ = 10002659 is a prime.

Together with 10002659, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10002667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5001330 + 5001331.

It is an arithmetic number, because the mean of its divisors is an integer number (5001331).

Almost surely, 2^10002661 is an apocalyptic number.

It is an amenable number.

10002661 is a deficient number, since it is larger than the sum of its proper divisors (1).

10002661 is an equidigital number, since it uses as much as digits as its factorization.

10002661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 10002661 is about 3162.6983732250. The cubic root of 10002661 is about 215.4625771441.

Adding to 10002661 its reverse (16620001), we get a palindrome (26622662).

The spelling of 10002661 in words is "ten million, two thousand, six hundred sixty-one".