21963201761 has 2 divisors, whose sum is σ = 21963201762. Its totient is φ = 21963201760.

The previous prime is 21963201737. The next prime is 21963201779. The reversal of 21963201761 is 16710236912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21420078736 + 543123025 = 146356^2 + 23305^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21963201761 is a prime.

It is a super-2 number, since 2×21963201761² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21963201061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10981600880 + 10981600881.

It is an arithmetic number, because the mean of its divisors is an integer number (10981600881).

Almost surely, 2^21963201761 is an apocalyptic number.

It is an amenable number.

21963201761 is a deficient number, since it is larger than the sum of its proper divisors (1).

21963201761 is an equidigital number, since it uses as much as digits as its factorization.

21963201761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 38.

The spelling of 21963201761 in words is "twenty-one billion, nine hundred sixty-three million, two hundred one thousand, seven hundred sixty-one".