1160921981 has 2 divisors, whose sum is σ = 1160921982. Its totient is φ = 1160921980.

The previous prime is 1160921947. The next prime is 1160921999. The reversal of 1160921981 is 1891290611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1122853081 + 38068900 = 33509^2 + 6170^2 .

It is a cyclic number.

It is not a de Polignac number, because 1160921981 - 2⁶ = 1160921917 is a prime.

It is a super-2 number, since 2×1160921981² = 2695479691937928722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1160921921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580460990 + 580460991.

It is an arithmetic number, because the mean of its divisors is an integer number (580460991).

Almost surely, 2^1160921981 is an apocalyptic number.

It is an amenable number.

1160921981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1160921981 is an equidigital number, since it uses as much as digits as its factorization.

1160921981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 38.

The square root of 1160921981 is about 34072.3051905796. The cubic root of 1160921981 is about 1050.9958748140.

The spelling of 1160921981 in words is "one billion, one hundred sixty million, nine hundred twenty-one thousand, nine hundred eighty-one".