2016981 has 20 divisors (see below), whose sum is σ = 3099052. Its totient is φ = 1306368.

The previous prime is 2016977. The next prime is 2016997. The reversal of 2016981 is 1896102.

It can be written as a sum of positive squares in 2 ways, for example, as 1285956 + 731025 = 1134^2 + 855^2 .

It is not a de Polignac number, because 2016981 - 2² = 2016977 is a prime.

It is a super-2 number, since 2×2016981² = 8136424708722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

2016981 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2016181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2661 + ... + 3333.

2^2016981 is an apocalyptic number.

It is an amenable number.

2016981 is a deficient number, since it is larger than the sum of its proper divisors (1082071).

2016981 is an equidigital number, since it uses as much as digits as its factorization.

2016981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722 (or 713 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 2016981 is about 1420.2045627303. The cubic root of 2016981 is about 126.3476792017.

The spelling of 2016981 in words is "two million, sixteen thousand, nine hundred eighty-one".