1085661558 has 48 divisors (see below), whose sum is σ = 2479276800. Its totient is φ = 342396720.

The previous prime is 1085661557. The next prime is 1085661623. The reversal of 1085661558 is 8551665801.

1085661558 is a `hidden beast` number, since 10 + 85 + 6 + 6 + 1 + 558 = 666.

It is a super-2 number, since 2×1085661558² = 2357322037037974728, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1085661553) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 351063 + ... + 354141.

It is an arithmetic number, because the mean of its divisors is an integer number (51651600).

Almost surely, 2^1085661558 is an apocalyptic number.

1085661558 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1085661558 is an abundant number, since it is smaller than the sum of its proper divisors (1393615242).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1085661558 is a wasteful number, since it uses less digits than its factorization.

1085661558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4137 (or 4134 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 45.

The square root of 1085661558 is about 32949.3787194842. The cubic root of 1085661558 is about 1027.7752458480.

The spelling of 1085661558 in words is "one billion, eighty-five million, six hundred sixty-one thousand, five hundred fifty-eight".