19121 has 2 divisors, whose sum is σ = 19122.
Its totient is φ = 19120.
The previous prime is 19087. The next prime is 19139. The reversal of 19121 is 12191.
It can be divided in two parts, 191 and 21, that added together give a palindrome (212).
It is a m-pointer prime, because the next prime (19139) can be obtained adding 19121 to its product of digits (18).
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 18496 + 625 = 136^2 + 25^2
It is a cyclic number.
It is not a de Polignac number, because 19121 - 210 = 18097 is a prime.
It is a super-2 number, since 2×191212 = 731225282, which contains 22 as substring.
It is a Chen prime.
It is an Ulam number.
It is a junction number, because it is equal to n+sod(n) for n = 19096 and 19105.
It is not a weakly prime, because it can be changed into another prime (19141) 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, 9560 + 9561.
It is an arithmetic number, because the mean of its divisors is an integer number (9561).
219121 is an apocalyptic number.
It is an amenable number.
19121 is a deficient number, since it is larger than the sum of its proper divisors (1).
19121 is an equidigital number, since it uses as much as digits as its factorization.
19121 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 18, while the sum is 14.
The square root of 19121 is about 138.2787040726.
The cubic root of 19121 is about 26.7405416819.
The spelling of 19121 in words is "nineteen thousand, one hundred twenty-one".