21101021219 has 4 divisors (see below), whose sum is σ = 21101335296. Its totient is φ = 21100707144.

The previous prime is 21101021203. The next prime is 21101021243. The reversal of 21101021219 is 91212010112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21101021219 - 2⁴ = 21101021203 is a prime.

It is a super-2 number, since 2×21101021219² (a number of 21 digits) contains 22 as substring.

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 21101021219.

It is not an unprimeable number, because it can be changed into a prime (21101011219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10979 + ... + 205724.

It is an arithmetic number, because the mean of its divisors is an integer number (5275333824).

Almost surely, 2^21101021219 is an apocalyptic number.

21101021219 is a deficient number, since it is larger than the sum of its proper divisors (314077).

21101021219 is an equidigital number, since it uses as much as digits as its factorization.

21101021219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314076.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 21101021219 in words is "twenty-one billion, one hundred one million, twenty-one thousand, two hundred nineteen".