1156561604091 has 24 divisors (see below), whose sum is σ = 1689622434864. Its totient is φ = 762278961600.

The previous prime is 1156561604069. The next prime is 1156561604119. The reversal of 1156561604091 is 1904061656511.

It is not a de Polignac number, because 1156561604091 - 2⁷ = 1156561603963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1156561604291) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 324301 + ... + 1555086.

It is an arithmetic number, because the mean of its divisors is an integer number (70400934786).

Almost surely, 2^{1156561604091} is an apocalyptic number.

1156561604091 is a deficient number, since it is larger than the sum of its proper divisors (533060830773).

1156561604091 is a wasteful number, since it uses less digits than its factorization.

1156561604091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1880171 (or 1880168 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The spelling of 1156561604091 in words is "one trillion, one hundred fifty-six billion, five hundred sixty-one million, six hundred four thousand, ninety-one".