1085991705 has 40 divisors (see below), whose sum is σ = 2061267912. Its totient is φ = 545121792.

The previous prime is 1085991653. The next prime is 1085991733. The reversal of 1085991705 is 5071995801.

It can be written as a sum of positive squares in 4 ways, for example, as 154032921 + 931958784 = 12411^2 + 30528^2 .

It is not a de Polignac number, because 1085991705 - 2¹¹ = 1085989657 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 71982 + ... + 85751.

Almost surely, 2^1085991705 is an apocalyptic number.

1085991705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1085991705 is a deficient number, since it is larger than the sum of its proper divisors (975276207).

1085991705 is a wasteful number, since it uses less digits than its factorization.

1085991705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157767 (or 157758 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 45.

The square root of 1085991705 is about 32954.3882510357. The cubic root of 1085991705 is about 1027.8794165945.

The spelling of 1085991705 in words is "one billion, eighty-five million, nine hundred ninety-one thousand, seven hundred five".