1561311752 has 128 divisors (see below), whose sum is σ = 3951763200. Its totient is φ = 558489600.

The previous prime is 1561311733. The next prime is 1561311769. The reversal of 1561311752 is 2571131651.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1929524 + ... + 1930332.

It is an arithmetic number, because the mean of its divisors is an integer number (30873150).

Almost surely, 2^1561311752 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561311752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1975881600).

1561311752 is an abundant number, since it is smaller than the sum of its proper divisors (2390451448).

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

1561311752 is a wasteful number, since it uses less digits than its factorization.

1561311752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1087 (or 1083 counting only the distinct ones).

The product of its digits is 6300, while the sum is 32.

The square root of 1561311752 is about 39513.4376130450. The cubic root of 1561311752 is about 1160.1029813449.

It can be divided in two parts, 1561 and 311752, that added together give a palindrome (313313).

The spelling of 1561311752 in words is "one billion, five hundred sixty-one million, three hundred eleven thousand, seven hundred fifty-two".