1163278391 has 12 divisors (see below), whose sum is σ = 1280090952. Its totient is φ = 1056330000.

The previous prime is 1163278381. The next prime is 1163278447. The reversal of 1163278391 is 1938723611.

It is a de Polignac number, because none of the positive numbers 2^k-1163278391 is a prime.

It is a super-2 number, since 2×1163278391² = 2706433229935097762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1163278381) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112541 + ... + 122441.

It is an arithmetic number, because the mean of its divisors is an integer number (106674246).

Almost surely, 2^1163278391 is an apocalyptic number.

1163278391 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1163278391 is a deficient number, since it is larger than the sum of its proper divisors (116812561).

1163278391 is an equidigital number, since it uses as much as digits as its factorization.

1163278391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10894 (or 10883 counting only the distinct ones).

The product of its digits is 54432, while the sum is 41.

The square root of 1163278391 is about 34106.8672117508. The cubic root of 1163278391 is about 1051.7064891607.

The spelling of 1163278391 in words is "one billion, one hundred sixty-three million, two hundred seventy-eight thousand, three hundred ninety-one".