1099208021 has 2 divisors, whose sum is σ = 1099208022. Its totient is φ = 1099208020.

The previous prime is 1099208009. The next prime is 1099208027. The reversal of 1099208021 is 1208029901.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 911134225 + 188073796 = 30185^2 + 13714^2 .

It is a cyclic number.

It is not a de Polignac number, because 1099208021 - 2¹⁴ = 1099191637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1099208027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 549604010 + 549604011.

It is an arithmetic number, because the mean of its divisors is an integer number (549604011).

Almost surely, 2^1099208021 is an apocalyptic number.

It is an amenable number.

1099208021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1099208021 is an equidigital number, since it uses as much as digits as its factorization.

1099208021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 1099208021 is about 33154.3062210627. The cubic root of 1099208021 is about 1032.0323153177.

The spelling of 1099208021 in words is "one billion, ninety-nine million, two hundred eight thousand, twenty-one".