21201011999969 has 2 divisors, whose sum is σ = 21201011999970. Its totient is φ = 21201011999968.

The previous prime is 21201011999933. The next prime is 21201012000011. The reversal of 21201011999969 is 96999911010212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18029050999969 + 3171961000000 = 4246063^2 + 1781000^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201011999969 - 2¹² = 21201011995873 is a prime.

It is a super-2 number, since 2×21201011999969² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21201011993969) 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, 10600505999984 + 10600505999985.

It is an arithmetic number, because the mean of its divisors is an integer number (10600505999985).

Almost surely, 2^{21201011999969} is an apocalyptic number.

It is an amenable number.

21201011999969 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201011999969 is an equidigital number, since it uses as much as digits as its factorization.

21201011999969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1417176, while the sum is 59.

The spelling of 21201011999969 in words is "twenty-one trillion, two hundred one billion, eleven million, nine hundred ninety-nine thousand, nine hundred sixty-nine".