21169219 has 2 divisors, whose sum is σ = 21169220. Its totient is φ = 21169218.

The previous prime is 21169157. The next prime is 21169229. The reversal of 21169219 is 91296112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21169219 - 2⁷ = 21169091 is a prime.

It is a super-2 number, since 2×21169219² = 896271666139922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21169229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10584609 + 10584610.

It is an arithmetic number, because the mean of its divisors is an integer number (10584610).

Almost surely, 2^21169219 is an apocalyptic number.

21169219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21169219 is an equidigital number, since it uses as much as digits as its factorization.

21169219 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 31.

The square root of 21169219 is about 4601.0019560961. The cubic root of 21169219 is about 276.6314874384.

The spelling of 21169219 in words is "twenty-one million, one hundred sixty-nine thousand, two hundred nineteen".