1561303500 has 96 divisors (see below), whose sum is σ = 4558794240. Its totient is φ = 415224000.

The previous prime is 1561303463. The next prime is 1561303507. The reversal of 1561303500 is 53031651.

It is a super-2 number, since 2×1561303500² = 4875337238224500000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1561303507) 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 31 ways as a sum of consecutive naturals, for example, 657315 + ... + 659685.

It is an arithmetic number, because the mean of its divisors is an integer number (47487440).

Almost surely, 2^1561303500 is an apocalyptic number.

1561303500 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 1561303500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2279397120).

1561303500 is an abundant number, since it is smaller than the sum of its proper divisors (2997490740).

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

1561303500 is a wasteful number, since it uses less digits than its factorization.

1561303500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2832 (or 2820 counting only the distinct ones).

The product of its (nonzero) digits is 1350, while the sum is 24.

The square root of 1561303500 is about 39513.3331927338. Note that the first 3 decimals coincide. The cubic root of 1561303500 is about 1160.1009375108.

The spelling of 1561303500 in words is "one billion, five hundred sixty-one million, three hundred three thousand, five hundred".