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BaseRepresentation
bin1010010000111110100101
312001201022222
422100332211
51142102411
6133402125
731605266
oct12207645
95051288
102690981
111578857
12a99345
13732ac7
1450096d
153824db
hex290fa5

2690981 has 4 divisors (see below), whose sum is σ = 2849292. Its totient is φ = 2532672.

The previous prime is 2690959. The next prime is 2690993. The reversal of 2690981 is 1890962.

2690981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1890962 = 2945481.

It can be written as a sum of positive squares in 2 ways, for example, as 2280100 + 410881 = 1510^2 + 641^2 .

It is a cyclic number.

It is not a de Polignac number, because 2690981 - 210 = 2689957 is a prime.

It is a super-2 number, since 2×26909812 = 14482757484722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2690911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79130 + ... + 79163.

It is an arithmetic number, because the mean of its divisors is an integer number (712323).

22690981 is an apocalyptic number.

It is an amenable number.

2690981 is a deficient number, since it is larger than the sum of its proper divisors (158311).

2690981 is a wasteful number, since it uses less digits than its factorization.

2690981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158310.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 2690981 is about 1640.4209825530. The cubic root of 2690981 is about 139.0924457919.

The spelling of 2690981 in words is "two million, six hundred ninety thousand, nine hundred eighty-one".

Divisors: 1 17 158293 2690981