1561223112 has 32 divisors (see below), whose sum is σ = 3904097280. Its totient is φ = 520269120.

The previous prime is 1561223107. The next prime is 1561223117. The reversal of 1561223112 is 2113221651.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1561223107) and next prime (1561223117).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (1561223117) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 126162 + ... + 137982.

It is an arithmetic number, because the mean of its divisors is an integer number (122003040).

Almost surely, 2^1561223112 is an apocalyptic number.

1561223112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1561223112 is an abundant number, since it is smaller than the sum of its proper divisors (2342874168).

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

1561223112 is a wasteful number, since it uses less digits than its factorization.

1561223112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17333 (or 17329 counting only the distinct ones).

The product of its digits is 720, while the sum is 24.

The square root of 1561223112 is about 39512.3159533834. The cubic root of 1561223112 is about 1160.0810268411.

Adding to 1561223112 its reverse (2113221651), we get a palindrome (3674444763).

The spelling of 1561223112 in words is "one billion, five hundred sixty-one million, two hundred twenty-three thousand, one hundred twelve".