125491871 has 4 divisors (see below), whose sum is σ = 127364952. Its totient is φ = 123618792.

The previous prime is 125491867. The next prime is 125491913. The reversal of 125491871 is 178194521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 178194521 = 19 ⋅9378659.

It is a cyclic number.

It is not a de Polignac number, because 125491871 - 2² = 125491867 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 (125491831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 936440 + ... + 936573.

It is an arithmetic number, because the mean of its divisors is an integer number (31841238).

Almost surely, 2^125491871 is an apocalyptic number.

125491871 is a deficient number, since it is larger than the sum of its proper divisors (1873081).

125491871 is an equidigital number, since it uses as much as digits as its factorization.

125491871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1873080.

The product of its digits is 20160, while the sum is 38.

The square root of 125491871 is about 11202.3154303028. The cubic root of 125491871 is about 500.6549696549.

The spelling of 125491871 in words is "one hundred twenty-five million, four hundred ninety-one thousand, eight hundred seventy-one".