1201111091 has 2 divisors, whose sum is σ = 1201111092. Its totient is φ = 1201111090.

The previous prime is 1201111019. The next prime is 1201111117. The reversal of 1201111091 is 1901111021.

It is a happy number.

Together with previous prime (1201111019) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1201111091 - 2¹⁸ = 1200848947 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1201119091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 600555545 + 600555546.

It is an arithmetic number, because the mean of its divisors is an integer number (600555546).

Almost surely, 2^1201111091 is an apocalyptic number.

1201111091 is a deficient number, since it is larger than the sum of its proper divisors (1).

1201111091 is an equidigital number, since it uses as much as digits as its factorization.

1201111091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 17.

The square root of 1201111091 is about 34657.0496580422. The cubic root of 1201111091 is about 1062.9864431130.

The spelling of 1201111091 in words is "one billion, two hundred one million, one hundred eleven thousand, ninety-one".