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BaseRepresentation
bin1101101101101
3100122001
41231231
5211041
652301
726320
oct15555
910561
107021
115303
124091
133271
1427b7
152131
hex1b6d

7021 has 8 divisors (see below), whose sum is σ = 8640. Its totient is φ = 5568.

The previous prime is 7019. The next prime is 7027. The reversal of 7021 is 1207.

7021 is a nontrivial binomial coefficient, being equal to C(119, 2).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7021 - 21 = 7019 is a prime.

It is a Duffinian number.

7021 is a modest number, since divided by 21 gives 7 as remainder.

It is a plaindrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 6989 and 7007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90 + ... + 148.

It is an arithmetic number, because the mean of its divisors is an integer number (1080).

7021 is the 118-th triangular number.

7021 is the 40-th centered nonagonal number.

It is an amenable number.

7021 is a deficient number, since it is larger than the sum of its proper divisors (1619).

7021 is a wasteful number, since it uses less digits than its factorization.

7021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83.

The product of its (nonzero) digits is 14, while the sum is 10.

The square root of 7021 is about 83.7914076741. The cubic root of 7021 is about 19.1484220421.

Subtracting from 7021 its product of nonzero digits (14), we obtain a palindrome (7007).

Adding to 7021 its reverse (1207), we get a palindrome (8228).

It can be divided in two parts, 702 and 1, that added together give a triangular number (703 = T37).

The spelling of 7021 in words is "seven thousand, twenty-one", and thus it is an iban number.

Divisors: 1 7 17 59 119 413 1003 7021