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BaseRepresentation
bin111001010000…
…1001111010001
32002111012110122
41302201033101
530141124221
62551240025
7513112334
oct162411721
962435418
1030020561
1115a4498a
12a079015
1362b145c
143db661b
15297eeab
hex1ca13d1

30020561 has 2 divisors, whose sum is σ = 30020562. Its totient is φ = 30020560.

The previous prime is 30020527. The next prime is 30020563. The reversal of 30020561 is 16502003.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27888961 + 2131600 = 5281^2 + 1460^2 .

It is a cyclic number.

It is not a de Polignac number, because 30020561 - 210 = 30019537 is a prime.

It is a Sophie Germain prime.

Together with 30020563, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (30020563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15010280 + 15010281.

It is an arithmetic number, because the mean of its divisors is an integer number (15010281).

Almost surely, 230020561 is an apocalyptic number.

It is an amenable number.

30020561 is a deficient number, since it is larger than the sum of its proper divisors (1).

30020561 is an equidigital number, since it uses as much as digits as its factorization.

30020561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 30020561 is about 5479.1022074789. The cubic root of 30020561 is about 310.7942208371.

Adding to 30020561 its reverse (16502003), we get a palindrome (46522564).

The spelling of 30020561 in words is "thirty million, twenty thousand, five hundred sixty-one".