1561352320 has 128 divisors (see below), whose sum is σ = 4105442880. Its totient is φ = 563097600.

The previous prime is 1561352269. The next prime is 1561352321. The reversal of 1561352320 is 232531651.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (1561352321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 921394 + ... + 923086.

Almost surely, 2^1561352320 is an apocalyptic number.

1561352320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561352320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2052721440).

1561352320 is an abundant number, since it is smaller than the sum of its proper divisors (2544090560).

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

1561352320 is a wasteful number, since it uses less digits than its factorization.

1561352320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1854 (or 1842 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 1561352320 is about 39513.9509540618. The cubic root of 1561352320 is about 1160.1130290179.

Adding to 1561352320 its reverse (232531651), we get a palindrome (1793883971).

The spelling of 1561352320 in words is "one billion, five hundred sixty-one million, three hundred fifty-two thousand, three hundred twenty".