105781609 has 2 divisors, whose sum is σ = 105781610. Its totient is φ = 105781608.

The previous prime is 105781561. The next prime is 105781619. The reversal of 105781609 is 906187501.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66781584 + 39000025 = 8172^2 + 6245^2 .

It is a cyclic number.

It is not a de Polignac number, because 105781609 - 2¹¹ = 105779561 is a prime.

It is a super-2 number, since 2×105781609² = 22379497605257762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (105781619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52890804 + 52890805.

It is an arithmetic number, because the mean of its divisors is an integer number (52890805).

Almost surely, 2^105781609 is an apocalyptic number.

It is an amenable number.

105781609 is a deficient number, since it is larger than the sum of its proper divisors (1).

105781609 is an equidigital number, since it uses as much as digits as its factorization.

105781609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 105781609 is about 10285.0186679461. The cubic root of 105781609 is about 472.9371060333.

The spelling of 105781609 in words is "one hundred five million, seven hundred eighty-one thousand, six hundred nine".