19810481 has 2 divisors, whose sum is σ = 19810482. Its totient is φ = 19810480.

The previous prime is 19810477. The next prime is 19810507. The reversal of 19810481 is 18401891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13256881 + 6553600 = 3641^2 + 2560^2 .

It is a cyclic number.

It is not a de Polignac number, because 19810481 - 2² = 19810477 is a prime.

It is a super-2 number, since 2×19810481² = 784910314902722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19810411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9905240 + 9905241.

It is an arithmetic number, because the mean of its divisors is an integer number (9905241).

Almost surely, 2^19810481 is an apocalyptic number.

It is an amenable number.

19810481 is a deficient number, since it is larger than the sum of its proper divisors (1).

19810481 is an equidigital number, since it uses as much as digits as its factorization.

19810481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 32.

The square root of 19810481 is about 4450.8966512378. The cubic root of 19810481 is about 270.5816495979.

The spelling of 19810481 in words is "nineteen million, eight hundred ten thousand, four hundred eighty-one".