1561013280 has 144 divisors (see below), whose sum is σ = 5337783360. Its totient is φ = 415425024.

The previous prime is 1561013221. The next prime is 1561013281. The reversal of 1561013280 is 823101651.

1561013280 is a `hidden beast` number, since 15 + 610 + 1 + 32 + 8 + 0 = 666.

1561013280 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (1561013281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1069191 + ... + 1070649.

It is an arithmetic number, because the mean of its divisors is an integer number (37067940).

Almost surely, 2^1561013280 is an apocalyptic number.

1561013280 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 1561013280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2668891680).

1561013280 is an abundant number, since it is smaller than the sum of its proper divisors (3776770080).

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

1561013280 is a wasteful number, since it uses less digits than its factorization.

1561013280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2223 (or 2212 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1561013280 is about 39509.6605907973. The cubic root of 1561013280 is about 1160.0290519874.

The spelling of 1561013280 in words is "one billion, five hundred sixty-one million, thirteen thousand, two hundred eighty".