1111099981 has 2 divisors, whose sum is σ = 1111099982. Its totient is φ = 1111099980.

The previous prime is 1111099961. The next prime is 1111100021. The reversal of 1111099981 is 1899901111.

It is an a-pointer prime, because the next prime (1111100021) can be obtained adding 1111099981 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1106626756 + 4473225 = 33266^2 + 2115^2 .

It is a cyclic number.

It is not a de Polignac number, because 1111099981 - 2⁷ = 1111099853 is a prime.

It is a super-2 number, since 2×1111099981² = 2469086335556400722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1111099921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 555549990 + 555549991.

It is an arithmetic number, because the mean of its divisors is an integer number (555549991).

Almost surely, 2^1111099981 is an apocalyptic number.

It is an amenable number.

1111099981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1111099981 is an equidigital number, since it uses as much as digits as its factorization.

1111099981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 40.

The square root of 1111099981 is about 33333.1663812486. The cubic root of 1111099981 is about 1035.7407102554.

The spelling of 1111099981 in words is "one billion, one hundred eleven million, ninety-nine thousand, nine hundred eighty-one".