2102200721 has 2 divisors, whose sum is σ = 2102200722. Its totient is φ = 2102200720.

The previous prime is 2102200699. The next prime is 2102200787. The reversal of 2102200721 is 1270022012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2088033025 + 14167696 = 45695^2 + 3764^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102200721 - 2¹⁸ = 2101938577 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2102200721.

It is not a weakly prime, because it can be changed into another prime (2102203721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1051100360 + 1051100361.

It is an arithmetic number, because the mean of its divisors is an integer number (1051100361).

Almost surely, 2^2102200721 is an apocalyptic number.

It is an amenable number.

2102200721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2102200721 is an equidigital number, since it uses as much as digits as its factorization.

2102200721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 2102200721 is about 45849.7624966586. The cubic root of 2102200721 is about 1281.0263417460.

Adding to 2102200721 its reverse (1270022012), we get a palindrome (3372222733).

The spelling of 2102200721 in words is "two billion, one hundred two million, two hundred thousand, seven hundred twenty-one".