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1831 is a prime number

1831 has 2 divisors, whose sum is σ = 1832. Its totient is φ = 1830.

The previous prime is 1823. The next prime is 1847. The reversal of 1831 is 1381.

1831 is nontrivially palindromic in base 2 and base 16.

It is a weak prime.

It is an emirp because it is prime and its reverse (1381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1831 - 23 = 1823 is a prime.

It is a super-2 number, since 2×18312 = 6705122, which contains 22 as substring.

It is a pancake number, because a pancake can be divided into 1831 parts by 60 straight cuts.

1831 is an undulating number in base 16.

1831 is a lucky number.

It is a plaindrome in base 8 and base 13.

It is a nialpdrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 915 + 916.

It is an arithmetic number, because the mean of its divisors is an integer number (916).

21831 is an apocalyptic number.

1831 is a deficient number, since it is larger than the sum of its proper divisors (1).

1831 is an equidigital number, since it uses as much as digits as its factorization.

1831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24, while the sum is 13.

The square root of 1831 is about 42.7901857907. The cubic root of 1831 is about 12.2338395816.

It can be divided in two parts, 18 and 31, that added together give a square (49 = 72).

The spelling of 1831 in words is "one thousand, eight hundred thirty-one".