104109781 has 2 divisors, whose sum is σ = 104109782. Its totient is φ = 104109780.

The previous prime is 104109779. The next prime is 104109787. The reversal of 104109781 is 187901401.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 101103025 + 3006756 = 10055^2 + 1734^2 .

It is a cyclic number.

It is not a de Polignac number, because 104109781 - 2¹ = 104109779 is a prime.

It is a super-2 number, since 2×104109781² = 21677692999735922, which contains 22 as substring.

Together with 104109779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (104109787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52054890 + 52054891.

It is an arithmetic number, because the mean of its divisors is an integer number (52054891).

Almost surely, 2^104109781 is an apocalyptic number.

It is an amenable number.

104109781 is a deficient number, since it is larger than the sum of its proper divisors (1).

104109781 is an equidigital number, since it uses as much as digits as its factorization.

104109781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 104109781 is about 10203.4200638805. The cubic root of 104109781 is about 470.4323485055.

The spelling of 104109781 in words is "one hundred four million, one hundred nine thousand, seven hundred eighty-one".