2051326661 has 2 divisors, whose sum is σ = 2051326662. Its totient is φ = 2051326660.

The previous prime is 2051326577. The next prime is 2051326663. The reversal of 2051326661 is 1666231502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2035724161 + 15602500 = 45119^2 + 3950^2 .

It is a cyclic number.

It is not a de Polignac number, because 2051326661 - 2¹⁰ = 2051325637 is a prime.

Together with 2051326663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2051326663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1025663330 + 1025663331.

It is an arithmetic number, because the mean of its divisors is an integer number (1025663331).

Almost surely, 2^2051326661 is an apocalyptic number.

It is an amenable number.

2051326661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2051326661 is an equidigital number, since it uses as much as digits as its factorization.

2051326661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 2051326661 is about 45291.5738410579. The cubic root of 2051326661 is about 1270.6080666391.

It can be divided in two parts, 20513 and 26661, that added together give a palindrome (47174).

The spelling of 2051326661 in words is "two billion, fifty-one million, three hundred twenty-six thousand, six hundred sixty-one".