1561561041 has 16 divisors (see below), whose sum is σ = 2134704384. Its totient is φ = 1014902784.

The previous prime is 1561561033. The next prime is 1561561049. The reversal of 1561561041 is 1401651651.

It is an interprime number because it is at equal distance from previous prime (1561561033) and next prime (1561561049).

It is not a de Polignac number, because 1561561041 - 2³ = 1561561033 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1561561049) 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, 14691 + ... + 57783.

It is an arithmetic number, because the mean of its divisors is an integer number (133419024).

Almost surely, 2^1561561041 is an apocalyptic number.

It is an amenable number.

1561561041 is a deficient number, since it is larger than the sum of its proper divisors (573143343).

1561561041 is a wasteful number, since it uses less digits than its factorization.

1561561041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43400.

The product of its (nonzero) digits is 3600, while the sum is 30.

The square root of 1561561041 is about 39516.5919709683. The cubic root of 1561561041 is about 1160.1647212080.

The spelling of 1561561041 in words is "one billion, five hundred sixty-one million, five hundred sixty-one thousand, forty-one".