1201009091 has 4 divisors (see below), whose sum is σ = 1217924784. Its totient is φ = 1184093400.

The previous prime is 1201009039. The next prime is 1201009109. The reversal of 1201009091 is 1909001021.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1201009091 - 2⁶ = 1201009027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1201006091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8457740 + ... + 8457881.

It is an arithmetic number, because the mean of its divisors is an integer number (304481196).

Almost surely, 2^1201009091 is an apocalyptic number.

1201009091 is a deficient number, since it is larger than the sum of its proper divisors (16915693).

1201009091 is an equidigital number, since it uses as much as digits as its factorization.

1201009091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16915692.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 1201009091 is about 34655.5780647214. The cubic root of 1201009091 is about 1062.9563521727.

The spelling of 1201009091 in words is "one billion, two hundred one million, nine thousand, ninety-one".