2110999981 has 2 divisors, whose sum is σ = 2110999982. Its totient is φ = 2110999980.

The previous prime is 2110999967. The next prime is 2111000009. The reversal of 2110999981 is 1899990112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1165129956 + 945870025 = 34134^2 + 30755^2 .

It is a cyclic number.

It is not a de Polignac number, because 2110999981 - 2⁵ = 2110999949 is a prime.

It is a super-2 number, since 2×2110999981² = 8912641839564000722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2110999951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1055499990 + 1055499991.

It is an arithmetic number, because the mean of its divisors is an integer number (1055499991).

Almost surely, 2^2110999981 is an apocalyptic number.

It is an amenable number.

2110999981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2110999981 is an equidigital number, since it uses as much as digits as its factorization.

2110999981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 49.

The square root of 2110999981 is about 45945.6198238744. The cubic root of 2110999981 is about 1282.8112003275.

The spelling of 2110999981 in words is "two billion, one hundred ten million, nine hundred ninety-nine thousand, nine hundred eighty-one".