1211022091 has 2 divisors, whose sum is σ = 1211022092. Its totient is φ = 1211022090.

The previous prime is 1211022083. The next prime is 1211022097. The reversal of 1211022091 is 1902201121.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1902201121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211022091 - 2³ = 1211022083 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211022097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605511045 + 605511046.

It is an arithmetic number, because the mean of its divisors is an integer number (605511046).

Almost surely, 2^1211022091 is an apocalyptic number.

1211022091 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211022091 is an equidigital number, since it uses as much as digits as its factorization.

1211022091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 19.

The square root of 1211022091 is about 34799.7426858303. The cubic root of 1211022091 is about 1065.9021915689.

The spelling of 1211022091 in words is "one billion, two hundred eleven million, twenty-two thousand, ninety-one".