1561132565 has 16 divisors (see below), whose sum is σ = 1938109440. Its totient is φ = 1205919360.

The previous prime is 1561132561. The next prime is 1561132597. The reversal of 1561132565 is 5652311651.

It is not a de Polignac number, because 1561132565 - 2² = 1561132561 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561132561) 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, 59816 + ... + 81854.

It is an arithmetic number, because the mean of its divisors is an integer number (121131840).

Almost surely, 2^1561132565 is an apocalyptic number.

It is an amenable number.

1561132565 is a deficient number, since it is larger than the sum of its proper divisors (376976875).

1561132565 is a wasteful number, since it uses less digits than its factorization.

1561132565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22532.

The product of its digits is 27000, while the sum is 35.

The square root of 1561132565 is about 39511.1701294710. The cubic root of 1561132565 is about 1160.0585991503.

The spelling of 1561132565 in words is "one billion, five hundred sixty-one million, one hundred thirty-two thousand, five hundred sixty-five".