125168509 has 8 divisors (see below), whose sum is σ = 126976248. Its totient is φ = 123371520.

The previous prime is 125168497. The next prime is 125168513. The reversal of 125168509 is 905861521.

It can be written as a sum of positive squares in 4 ways, for example, as 80946009 + 44222500 = 8997^2 + 6650^2 .

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 125168509 - 2⁹ = 125167997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125168539) 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, 22419 + ... + 27439.

It is an arithmetic number, because the mean of its divisors is an integer number (15872031).

Almost surely, 2^125168509 is an apocalyptic number.

It is an amenable number.

125168509 is a deficient number, since it is larger than the sum of its proper divisors (1807739).

125168509 is an equidigital number, since it uses as much as digits as its factorization.

125168509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5375.

The product of its (nonzero) digits is 21600, while the sum is 37.

The square root of 125168509 is about 11187.8733010345. The cubic root of 125168509 is about 500.2245777812.

It can be divided in two parts, 12516 and 8509, that added together give a square (21025 = 145²).

The spelling of 125168509 in words is "one hundred twenty-five million, one hundred sixty-eight thousand, five hundred nine".