1561266125 has 16 divisors (see below), whose sum is σ = 1950723840. Its totient is φ = 1247562000.

The previous prime is 1561266089. The next prime is 1561266131. The reversal of 1561266125 is 5216621651.

It is not a de Polignac number, because 1561266125 - 2⁸ = 1561265869 is a prime.

It is a congruent number.

It is an unprimeable number.

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, 108080 + ... + 121670.

It is an arithmetic number, because the mean of its divisors is an integer number (121920240).

Almost surely, 2^1561266125 is an apocalyptic number.

It is an amenable number.

1561266125 is a deficient number, since it is larger than the sum of its proper divisors (389457715).

1561266125 is an equidigital number, since it uses as much as digits as its factorization.

1561266125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14525 (or 14515 counting only the distinct ones).

The product of its digits is 21600, while the sum is 35.

The square root of 1561266125 is about 39512.8602482787. The cubic root of 1561266125 is about 1160.0916804768.

Adding to 1561266125 its reverse (5216621651), we get a palindrome (6777887776).

The spelling of 1561266125 in words is "one billion, five hundred sixty-one million, two hundred sixty-six thousand, one hundred twenty-five".