1099725561 has 36 divisors (see below), whose sum is σ = 1756774656. Its totient is φ = 662399760.

The previous prime is 1099725553. The next prime is 1099725593. The reversal of 1099725561 is 1655279901.

1099725561 is a `hidden beast` number, since 1 + 0 + 9 + 97 + 2 + 556 + 1 = 666.

1099725561 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1099725561 - 2³ = 1099725553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1099725521) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 178840 + ... + 184886.

It is an arithmetic number, because the mean of its divisors is an integer number (48799296).

Almost surely, 2^1099725561 is an apocalyptic number.

1099725561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1099725561 is a deficient number, since it is larger than the sum of its proper divisors (657049095).

1099725561 is a wasteful number, since it uses less digits than its factorization.

1099725561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6242 (or 6228 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 45.

The square root of 1099725561 is about 33162.1103218719. The cubic root of 1099725561 is about 1032.1942604606.

The spelling of 1099725561 in words is "one billion, ninety-nine million, seven hundred twenty-five thousand, five hundred sixty-one".