1617663397091 has 4 divisors (see below), whose sum is σ = 1848758168112. Its totient is φ = 1386568626072.

The previous prime is 1617663397057. The next prime is 1617663397109. The reversal of 1617663397091 is 1907933667161.

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

It is not a de Polignac number, because 1617663397091 - 2¹⁰ = 1617663396067 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1617663397091.

It is not an unprimeable number, because it can be changed into a prime (1617663399091) 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, 115547385500 + ... + 115547385513.

It is an arithmetic number, because the mean of its divisors is an integer number (462189542028).

Almost surely, 2^{1617663397091} is an apocalyptic number.

1617663397091 is a deficient number, since it is larger than the sum of its proper divisors (231094771021).

1617663397091 is an equidigital number, since it uses as much as digits as its factorization.

1617663397091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231094771020.

The product of its (nonzero) digits is 7715736, while the sum is 59.

The spelling of 1617663397091 in words is "one trillion, six hundred seventeen billion, six hundred sixty-three million, three hundred ninety-seven thousand, ninety-one".