2105221751 has 2 divisors, whose sum is σ = 2105221752. Its totient is φ = 2105221750.

The previous prime is 2105221747. The next prime is 2105221757. The reversal of 2105221751 is 1571225012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2105221751 - 2² = 2105221747 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2105221751.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2105221757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1052610875 + 1052610876.

It is an arithmetic number, because the mean of its divisors is an integer number (1052610876).

Almost surely, 2^2105221751 is an apocalyptic number.

2105221751 is a deficient number, since it is larger than the sum of its proper divisors (1).

2105221751 is an equidigital number, since it uses as much as digits as its factorization.

2105221751 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1400, while the sum is 26.

The square root of 2105221751 is about 45882.6955507193. The cubic root of 2105221751 is about 1281.6396936819.

Adding to 2105221751 its reverse (1571225012), we get a palindrome (3676446763).

The spelling of 2105221751 in words is "two billion, one hundred five million, two hundred twenty-one thousand, seven hundred fifty-one".