21969219 has 8 divisors (see below), whose sum is σ = 31015440. Its totient is φ = 13784576.

The previous prime is 21969203. The next prime is 21969221. The reversal of 21969219 is 91296912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21969219 - 2⁴ = 21969203 is a prime.

It is a super-2 number, since 2×21969219² = 965293166939922, which contains 22 as substring.

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (21969229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 215334 + ... + 215435.

It is an arithmetic number, because the mean of its divisors is an integer number (3876930).

Almost surely, 2^21969219 is an apocalyptic number.

21969219 is a deficient number, since it is larger than the sum of its proper divisors (9046221).

21969219 is a wasteful number, since it uses less digits than its factorization.

21969219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430789.

The product of its digits is 17496, while the sum is 39.

The square root of 21969219 is about 4687.1333456602. The cubic root of 21969219 is about 280.0731909005.

The spelling of 21969219 in words is "twenty-one million, nine hundred sixty-nine thousand, two hundred nineteen".