1561534013 has 8 divisors (see below), whose sum is σ = 1682078328. Its totient is φ = 1441050624.

The previous prime is 1561534003. The next prime is 1561534049. The reversal of 1561534013 is 3104351651.

It can be written as a sum of positive squares in 4 ways, for example, as 114340249 + 1447193764 = 10693^2 + 38042^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1561534013 - 2¹⁰ = 1561532989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561534003) 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 7 ways as a sum of consecutive naturals, for example, 47645 + ... + 73437.

It is an arithmetic number, because the mean of its divisors is an integer number (210259791).

Almost surely, 2^1561534013 is an apocalyptic number.

1561534013 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1561534013 is a deficient number, since it is larger than the sum of its proper divisors (120544315).

1561534013 is a wasteful number, since it uses less digits than its factorization.

1561534013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30463.

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 1561534013 is about 39516.2499865562. The cubic root of 1561534013 is about 1160.1580276682.

Adding to 1561534013 its reverse (3104351651), we get a palindrome (4665885664).

The spelling of 1561534013 in words is "one billion, five hundred sixty-one million, five hundred thirty-four thousand, thirteen".