21174366361 has 2 divisors, whose sum is σ = 21174366362. Its totient is φ = 21174366360.

The previous prime is 21174366331. The next prime is 21174366379. The reversal of 21174366361 is 16366347112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18317998336 + 2856368025 = 135344^2 + 53445^2 .

It is a cyclic number.

It is not a de Polignac number, because 21174366361 - 2⁷ = 21174366233 is a prime.

It is not a weakly prime, because it can be changed into another prime (21174366331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10587183180 + 10587183181.

It is an arithmetic number, because the mean of its divisors is an integer number (10587183181).

Almost surely, 2^21174366361 is an apocalyptic number.

It is an amenable number.

21174366361 is a deficient number, since it is larger than the sum of its proper divisors (1).

21174366361 is an equidigital number, since it uses as much as digits as its factorization.

21174366361 is an odious number, because the sum of its binary digits is odd.

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

The spelling of 21174366361 in words is "twenty-one billion, one hundred seventy-four million, three hundred sixty-six thousand, three hundred sixty-one".