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30391261 is a prime number
BaseRepresentation
bin111001111101…
…1101111011101
32010012000222021
41303323233131
530240010021
63003220141
7516215155
oct163735735
963160867
1030391261
111617844a
12a217651
1363b10c4
144071765
152a04c41
hex1cfbbdd

30391261 has 2 divisors, whose sum is σ = 30391262. Its totient is φ = 30391260.

The previous prime is 30391247. The next prime is 30391289. The reversal of 30391261 is 16219303.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22382361 + 8008900 = 4731^2 + 2830^2 .

It is an emirp because it is prime and its reverse (16219303) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 30391261 - 217 = 30260189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30391201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15195630 + 15195631.

It is an arithmetic number, because the mean of its divisors is an integer number (15195631).

Almost surely, 230391261 is an apocalyptic number.

It is an amenable number.

30391261 is a deficient number, since it is larger than the sum of its proper divisors (1).

30391261 is an equidigital number, since it uses as much as digits as its factorization.

30391261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 30391261 is about 5512.8269517553. The cubic root of 30391261 is about 312.0682412915.

The spelling of 30391261 in words is "thirty million, three hundred ninety-one thousand, two hundred sixty-one".