2105203602221 has 4 divisors (see below), whose sum is σ = 2229039108252. Its totient is φ = 1981368096192.

The previous prime is 2105203602211. The next prime is 2105203602277. The reversal of 2105203602221 is 1222063025012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1510099357321 + 595104244900 = 1228861^2 + 771430^2 .

It is a cyclic number.

It is not a de Polignac number, because 2105203602221 - 2²² = 2105199407917 is a prime.

It is a super-2 number, since 2×2105203602221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2105203602211) 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, 61917752990 + ... + 61917753023.

It is an arithmetic number, because the mean of its divisors is an integer number (557259777063).

Almost surely, 2^{2105203602221} is an apocalyptic number.

It is an amenable number.

2105203602221 is a deficient number, since it is larger than the sum of its proper divisors (123835506031).

2105203602221 is a wasteful number, since it uses less digits than its factorization.

2105203602221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123835506030.

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 2105203602221 its reverse (1222063025012), we get a palindrome (3327266627233).

The spelling of 2105203602221 in words is "two trillion, one hundred five billion, two hundred three million, six hundred two thousand, two hundred twenty-one".