21099599663 has 2 divisors, whose sum is σ = 21099599664. Its totient is φ = 21099599662.

The previous prime is 21099599593. The next prime is 21099599669. The reversal of 21099599663 is 36699599012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21099599663 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21099599669) 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, 10549799831 + 10549799832.

It is an arithmetic number, because the mean of its divisors is an integer number (10549799832).

Almost surely, 2^21099599663 is an apocalyptic number.

21099599663 is a deficient number, since it is larger than the sum of its proper divisors (1).

21099599663 is an equidigital number, since it uses as much as digits as its factorization.

21099599663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7085880, while the sum is 59.

The spelling of 21099599663 in words is "twenty-one billion, ninety-nine million, five hundred ninety-nine thousand, six hundred sixty-three".