21002120219 has 16 divisors (see below), whose sum is σ = 21959024640. Its totient is φ = 20063090880.

The previous prime is 21002120213. The next prime is 21002120257. The reversal of 21002120219 is 91202120012.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-21002120219 is a prime.

It is a super-5 number, since 5×21002120219⁵ (a number of 53 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21002120219.

It is not an unprimeable number, because it can be changed into a prime (21002120213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4029287 + ... + 4034495.

It is an arithmetic number, because the mean of its divisors is an integer number (1372439040).

Almost surely, 2^21002120219 is an apocalyptic number.

21002120219 is a deficient number, since it is larger than the sum of its proper divisors (956904421).

21002120219 is a wasteful number, since it uses less digits than its factorization.

21002120219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6890.

The product of its (nonzero) digits is 144, while the sum is 20.

The spelling of 21002120219 in words is "twenty-one billion, two million, one hundred twenty thousand, two hundred nineteen".