125608921 has 4 divisors (see below), whose sum is σ = 125633700. Its totient is φ = 125584144.

The previous prime is 125608919. The next prime is 125608927. The reversal of 125608921 is 129806521.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21344400 + 104264521 = 4620^2 + 10211^2 .

It is a cyclic number.

It is not a de Polignac number, because 125608921 - 2¹ = 125608919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125608927) 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, 1726 + ... + 15943.

It is an arithmetic number, because the mean of its divisors is an integer number (31408425).

Almost surely, 2^125608921 is an apocalyptic number.

It is an amenable number.

125608921 is a deficient number, since it is larger than the sum of its proper divisors (24779).

125608921 is an equidigital number, since it uses as much as digits as its factorization.

125608921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24778.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 125608921 is about 11207.5385790101. The cubic root of 125608921 is about 500.8105798771.

The spelling of 125608921 in words is "one hundred twenty-five million, six hundred eight thousand, nine hundred twenty-one".