125640257 has 4 divisors (see below), whose sum is σ = 127230720. Its totient is φ = 124049796.

The previous prime is 125640253. The next prime is 125640269. The reversal of 125640257 is 752046521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 752046521 = 53 ⋅14189557.

It is a cyclic number.

It is not a de Polignac number, because 125640257 - 2² = 125640253 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125640253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 795113 + ... + 795270.

It is an arithmetic number, because the mean of its divisors is an integer number (31807680).

Almost surely, 2^125640257 is an apocalyptic number.

It is an amenable number.

125640257 is a deficient number, since it is larger than the sum of its proper divisors (1590463).

125640257 is an equidigital number, since it uses as much as digits as its factorization.

125640257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1590462.

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 125640257 is about 11208.9364794346. The cubic root of 125640257 is about 500.8522226080.

Adding to 125640257 its reverse (752046521), we get a palindrome (877686778).

The spelling of 125640257 in words is "one hundred twenty-five million, six hundred forty thousand, two hundred fifty-seven".