125666521 has 8 divisors (see below), whose sum is σ = 128024064. Its totient is φ = 123325440.

The previous prime is 125666491. The next prime is 125666531.

125666521 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 125666521 - 2¹³ = 125658329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125666531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11865 + ... + 19801.

It is an arithmetic number, because the mean of its divisors is an integer number (16003008).

Almost surely, 2^125666521 is an apocalyptic number.

It is an amenable number.

125666521 is a deficient number, since it is larger than the sum of its proper divisors (2357543).

125666521 is an equidigital number, since it uses as much as digits as its factorization.

125666521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8231.

The product of its digits is 21600, while the sum is 34.

The square root of 125666521 is about 11210.1079834228. The cubic root of 125666521 is about 500.8871197728.

The spelling of 125666521 in words is "one hundred twenty-five million, six hundred sixty-six thousand, five hundred twenty-one".