21000202169 has 2 divisors, whose sum is σ = 21000202170. Its totient is φ = 21000202168.

The previous prime is 21000202163. The next prime is 21000202213. The reversal of 21000202169 is 96120200012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13077066025 + 7923136144 = 114355^2 + 89012^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000202169 - 2⁸ = 21000201913 is a prime.

It is a super-2 number, since 2×21000202169² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21000202163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500101084 + 10500101085.

It is an arithmetic number, because the mean of its divisors is an integer number (10500101085).

Almost surely, 2^21000202169 is an apocalyptic number.

It is an amenable number.

21000202169 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000202169 is an equidigital number, since it uses as much as digits as its factorization.

21000202169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 23.

The spelling of 21000202169 in words is "twenty-one billion, two hundred two thousand, one hundred sixty-nine".