125566639 has 8 divisors (see below), whose sum is σ = 137587968. Its totient is φ = 113646360.

The previous prime is 125566631. The next prime is 125566663. The reversal of 125566639 is 936665521.

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 125566639 - 2³ = 125566631 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 125566595 and 125566604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125566631) 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, 22647 + ... + 27640.

It is an arithmetic number, because the mean of its divisors is an integer number (17198496).

Almost surely, 2^125566639 is an apocalyptic number.

125566639 is a deficient number, since it is larger than the sum of its proper divisors (12021329).

125566639 is a wasteful number, since it uses less digits than its factorization.

125566639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50525.

The product of its digits is 291600, while the sum is 43.

The square root of 125566639 is about 11205.6521006142. The cubic root of 125566639 is about 500.7543799161.

The spelling of 125566639 in words is "one hundred twenty-five million, five hundred sixty-six thousand, six hundred thirty-nine".