1171981355 has 4 divisors (see below), whose sum is σ = 1406377632. Its totient is φ = 937585080.

The previous prime is 1171981289. The next prime is 1171981357. The reversal of 1171981355 is 5531891711.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5531891711 = 131 ⋅42228181.

It is not a de Polignac number, because 1171981355 - 2⁸ = 1171981099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1171981357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117198131 + ... + 117198140.

It is an arithmetic number, because the mean of its divisors is an integer number (351594408).

Almost surely, 2^1171981355 is an apocalyptic number.

1171981355 is a deficient number, since it is larger than the sum of its proper divisors (234396277).

1171981355 is an equidigital number, since it uses as much as digits as its factorization.

1171981355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234396276.

The product of its digits is 37800, while the sum is 41.

The square root of 1171981355 is about 34234.2132230317. The cubic root of 1171981355 is about 1054.3227251623.

The spelling of 1171981355 in words is "one billion, one hundred seventy-one million, nine hundred eighty-one thousand, three hundred fifty-five".