21222019 has 16 divisors (see below), whose sum is σ = 26389440. Its totient is φ = 16617600.

The previous prime is 21222013. The next prime is 21222023. The reversal of 21222019 is 91022212.

21222019 is nontrivially palindromic in base 12.

It is a cyclic number.

It is not a de Polignac number, because 21222019 - 2¹⁷ = 21090947 is a prime.

It is a super-2 number, since 2×21222019² = 900748180872722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21221987 and 21222005.

It is not an unprimeable number, because it can be changed into a prime (21222013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8037 + ... + 10345.

It is an arithmetic number, because the mean of its divisors is an integer number (1649340).

Almost surely, 2^21222019 is an apocalyptic number.

21222019 is a deficient number, since it is larger than the sum of its proper divisors (5167421).

21222019 is a wasteful number, since it uses less digits than its factorization.

21222019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2430.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 21222019 is about 4606.7362633431. The cubic root of 21222019 is about 276.8612867499.

The spelling of 21222019 in words is "twenty-one million, two hundred twenty-two thousand, nineteen".