1561236480 has 264 divisors, whose sum is σ = 5730732072. Its totient is φ = 391643136.

The previous prime is 1561236461. The next prime is 1561236503. The reversal of 1561236480 is 846321651.

It is a happy number.

1561236480 is a `hidden beast` number, since 1 + 5 + 6 + 1 + 2 + 3 + 648 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 483296256 + 1077940224 = 21984^2 + 32832^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 782364 + ... + 784356.

Almost surely, 2^1561236480 is an apocalyptic number.

1561236480 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 1561236480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2865366036).

1561236480 is an abundant number, since it is smaller than the sum of its proper divisors (4169495592).

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

1561236480 is a wasteful number, since it uses less digits than its factorization.

1561236480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2041 (or 2020 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 1561236480 is about 39512.4851154670. The cubic root of 1561236480 is about 1160.0843379029.

The spelling of 1561236480 in words is "one billion, five hundred sixty-one million, two hundred thirty-six thousand, four hundred eighty".