1561147120 has 80 divisors (see below), whose sum is σ = 3945684960. Its totient is φ = 570995712.

The previous prime is 1561147117. The next prime is 1561147123. The reversal of 1561147120 is 217411651.

It is an interprime number because it is at equal distance from previous prime (1561147117) and next prime (1561147123).

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561147123) 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, 104266 + ... + 118294.

It is an arithmetic number, because the mean of its divisors is an integer number (49321062).

Almost surely, 2^1561147120 is an apocalyptic number.

1561147120 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 1561147120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1972842480).

1561147120 is an abundant number, since it is smaller than the sum of its proper divisors (2384537840).

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

1561147120 is a wasteful number, since it uses less digits than its factorization.

1561147120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14162 (or 14156 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 1561147120 is about 39511.3543174617. The cubic root of 1561147120 is about 1160.0622043535.

Adding to 1561147120 its reverse (217411651), we get a palindrome (1778558771).

The spelling of 1561147120 in words is "one billion, five hundred sixty-one million, one hundred forty-seven thousand, one hundred twenty".