125144561 has 4 divisors (see below), whose sum is σ = 125201892. Its totient is φ = 125087232.

The previous prime is 125144521. The next prime is 125144573. The reversal of 125144561 is 165441521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165441521 = 7 ⋅23634503.

It can be written as a sum of positive squares in 2 ways, for example, as 66912400 + 58232161 = 8180^2 + 7631^2 .

It is a cyclic number.

It is not a de Polignac number, because 125144561 - 2¹⁰ = 125143537 is a prime.

It is a super-2 number, since 2×125144561² = 31322322295765442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125144521) 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, 25256 + ... + 29801.

It is an arithmetic number, because the mean of its divisors is an integer number (31300473).

Almost surely, 2^125144561 is an apocalyptic number.

It is an amenable number.

125144561 is a deficient number, since it is larger than the sum of its proper divisors (57331).

125144561 is an equidigital number, since it uses as much as digits as its factorization.

125144561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57330.

The product of its digits is 4800, while the sum is 29.

The square root of 125144561 is about 11186.8029838735. The cubic root of 125144561 is about 500.1926737441.

The spelling of 125144561 in words is "one hundred twenty-five million, one hundred forty-four thousand, five hundred sixty-one".