1561000122 has 24 divisors (see below), whose sum is σ = 3689637120. Its totient is φ = 473030280.

The previous prime is 1561000117. The next prime is 1561000153. The reversal of 1561000122 is 2210001651.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1561000095 and 1561000104.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3941722 + ... + 3942117.

It is an arithmetic number, because the mean of its divisors is an integer number (153734880).

Almost surely, 2^1561000122 is an apocalyptic number.

1561000122 is an abundant number, since it is smaller than the sum of its proper divisors (2128636998).

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

1561000122 is a wasteful number, since it uses less digits than its factorization.

1561000122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7883858 (or 7883855 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 1561000122 is about 39509.4940742096. The cubic root of 1561000122 is about 1160.0257926290.

Adding to 1561000122 its reverse (2210001651), we get a palindrome (3771001773).

The spelling of 1561000122 in words is "one billion, five hundred sixty-one million, one hundred twenty-two", and thus it is an aban number.