1561242515 has 16 divisors (see below), whose sum is σ = 2267082432. Its totient is φ = 1007591424.

The previous prime is 1561242511. The next prime is 1561242517. The reversal of 1561242515 is 5152421651.

It is not a de Polignac number, because 1561242515 - 2² = 1561242511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1561242511) 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 15 ways as a sum of consecutive naturals, for example, 1311374 + ... + 1312563.

It is an arithmetic number, because the mean of its divisors is an integer number (141692652).

Almost surely, 2^1561242515 is an apocalyptic number.

1561242515 is a deficient number, since it is larger than the sum of its proper divisors (705839917).

1561242515 is a wasteful number, since it uses less digits than its factorization.

1561242515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2623966.

The product of its digits is 12000, while the sum is 32.

The square root of 1561242515 is about 39512.5614836599. The cubic root of 1561242515 is about 1160.0858326797.

The spelling of 1561242515 in words is "one billion, five hundred sixty-one million, two hundred forty-two thousand, five hundred fifteen".