1118978281 has 4 divisors (see below), whose sum is σ = 1120493200. Its totient is φ = 1117463364.

The previous prime is 1118978279. The next prime is 1118978291. The reversal of 1118978281 is 1828798111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1828798111 = 7 ⋅261256873.

It is a cyclic number.

It is not a de Polignac number, because 1118978281 - 2¹ = 1118978279 is a prime.

It is a super-2 number, since 2×1118978281² = 2504224786699429922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1118978251) 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, 756351 + ... + 757828.

It is an arithmetic number, because the mean of its divisors is an integer number (280123300).

Almost surely, 2^1118978281 is an apocalyptic number.

It is an amenable number.

1118978281 is a deficient number, since it is larger than the sum of its proper divisors (1514919).

1118978281 is an equidigital number, since it uses as much as digits as its factorization.

1118978281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1514918.

The product of its digits is 64512, while the sum is 46.

The square root of 1118978281 is about 33451.1327311946. The cubic root of 1118978281 is about 1038.1829344213.

The spelling of 1118978281 in words is "one billion, one hundred eighteen million, nine hundred seventy-eight thousand, two hundred eighty-one".