16220376661 has 2 divisors, whose sum is σ = 16220376662. Its totient is φ = 16220376660.

The previous prime is 16220376643. The next prime is 16220376671. The reversal of 16220376661 is 16667302261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11945178436 + 4275198225 = 109294^2 + 65385^2 .

It is a cyclic number.

It is not a de Polignac number, because 16220376661 - 2²³ = 16211988053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16220376671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8110188330 + 8110188331.

It is an arithmetic number, because the mean of its divisors is an integer number (8110188331).

Almost surely, 2^16220376661 is an apocalyptic number.

It is an amenable number.

16220376661 is a deficient number, since it is larger than the sum of its proper divisors (1).

16220376661 is an equidigital number, since it uses as much as digits as its factorization.

16220376661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 40.

The spelling of 16220376661 in words is "sixteen billion, two hundred twenty million, three hundred seventy-six thousand, six hundred sixty-one".