21273169 has 2 divisors, whose sum is σ = 21273170. Its totient is φ = 21273168.

The previous prime is 21273157. The next prime is 21273181. The reversal of 21273169 is 96137212.

It is a balanced prime because it is at equal distance from previous prime (21273157) and next prime (21273181).

It can be written as a sum of positive squares in only one way, i.e., 14922769 + 6350400 = 3863^2 + 2520^2 .

It is a cyclic number.

It is not a de Polignac number, because 21273169 - 2¹⁹ = 20748881 is a prime.

It is a super-2 number, since 2×21273169² = 905095438605122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21273169.

It is not a weakly prime, because it can be changed into another prime (21273139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10636584 + 10636585.

It is an arithmetic number, because the mean of its divisors is an integer number (10636585).

Almost surely, 2^21273169 is an apocalyptic number.

It is an amenable number.

21273169 is a deficient number, since it is larger than the sum of its proper divisors (1).

21273169 is an equidigital number, since it uses as much as digits as its factorization.

21273169 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 31.

The square root of 21273169 is about 4612.2845749151. The cubic root of 21273169 is about 277.0835416409.

The spelling of 21273169 in words is "twenty-one million, two hundred seventy-three thousand, one hundred sixty-nine".