1561231122 has 32 divisors (see below), whose sum is σ = 3554426880. Its totient is φ = 452530320.

The previous prime is 1561231117. The next prime is 1561231127. The reversal of 1561231122 is 2211321651.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1561231117) and next prime (1561231127).

It is a junction number, because it is equal to n+sod(n) for n = 1561231092 and 1561231101.

It is not an unprimeable number, because it can be changed into a prime (1561231127) 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 15 ways as a sum of consecutive naturals, for example, 512722 + ... + 515757.

It is an arithmetic number, because the mean of its divisors is an integer number (111075840).

Almost surely, 2^1561231122 is an apocalyptic number.

1561231122 is an abundant number, since it is smaller than the sum of its proper divisors (1993195758).

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

1561231122 is a wasteful number, since it uses less digits than its factorization.

1561231122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1028518.

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

The square root of 1561231122 is about 39512.4173140546. The cubic root of 1561231122 is about 1160.0830108055.

Adding to 1561231122 its reverse (2211321651), we get a palindrome (3772552773).

The spelling of 1561231122 in words is "one billion, five hundred sixty-one million, two hundred thirty-one thousand, one hundred twenty-two".