125781785 has 4 divisors (see below), whose sum is σ = 150938148. Its totient is φ = 100625424.

The previous prime is 125781781. The next prime is 125781791. The reversal of 125781785 is 587187521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 587187521 = 37 ⋅15869933.

It can be written as a sum of positive squares in 2 ways, for example, as 50993881 + 74787904 = 7141^2 + 8648^2 .

It is a cyclic number.

It is not a de Polignac number, because 125781785 - 2² = 125781781 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125781781) 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 3 ways as a sum of consecutive naturals, for example, 12578174 + ... + 12578183.

It is an arithmetic number, because the mean of its divisors is an integer number (37734537).

Almost surely, 2^125781785 is an apocalyptic number.

It is an amenable number.

125781785 is a deficient number, since it is larger than the sum of its proper divisors (25156363).

125781785 is an equidigital number, since it uses as much as digits as its factorization.

125781785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25156362.

The product of its digits is 156800, while the sum is 44.

The square root of 125781785 is about 11215.2478795611. The cubic root of 125781785 is about 501.0402144072.

The spelling of 125781785 in words is "one hundred twenty-five million, seven hundred eighty-one thousand, seven hundred eighty-five".