1180447981 has 4 divisors (see below), whose sum is σ = 1183951132. Its totient is φ = 1176944832.

The previous prime is 1180447967. The next prime is 1180447993. The reversal of 1180447981 is 1897440811.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 591948900 + 588499081 = 24330^2 + 24259^2 .

It is a cyclic number.

It is not a de Polignac number, because 1180447981 - 2¹³ = 1180439789 is a prime.

It is a super-2 number, since 2×1180447981² = 2786914871693952722, 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 (1180447951) 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, 1751070 + ... + 1751743.

It is an arithmetic number, because the mean of its divisors is an integer number (295987783).

Almost surely, 2^1180447981 is an apocalyptic number.

It is an amenable number.

1180447981 is a deficient number, since it is larger than the sum of its proper divisors (3503151).

1180447981 is an equidigital number, since it uses as much as digits as its factorization.

1180447981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3503150.

The product of its (nonzero) digits is 64512, while the sum is 43.

The square root of 1180447981 is about 34357.6480714265. The cubic root of 1180447981 is about 1056.8555146928.

It can be divided in two parts, 118044 and 7981, that added together give a square (126025 = 355²).

The spelling of 1180447981 in words is "one billion, one hundred eighty million, four hundred forty-seven thousand, nine hundred eighty-one".