21103330021021 has 4 divisors (see below), whose sum is σ = 21103339214272. Its totient is φ = 21103320827772.

The previous prime is 21103330020991. The next prime is 21103330021073. The reversal of 21103330021021 is 12012003330112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21103330021021 - 2¹⁵ = 21103329988253 is a prime.

It is a super-2 number, since 2×21103330021021² (a number of 27 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 21103330021021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103330421021) 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, 2058166 + ... + 6814888.

It is an arithmetic number, because the mean of its divisors is an integer number (5275834803568).

Almost surely, 2^{21103330021021} is an apocalyptic number.

It is an amenable number.

21103330021021 is a deficient number, since it is larger than the sum of its proper divisors (9193251).

21103330021021 is an equidigital number, since it uses as much as digits as its factorization.

21103330021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9193250.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21103330021021 its reverse (12012003330112), we get a palindrome (33115333351133).

The spelling of 21103330021021 in words is "twenty-one trillion, one hundred three billion, three hundred thirty million, twenty-one thousand, twenty-one".