125171661 has 4 divisors (see below), whose sum is σ = 166895552. Its totient is φ = 83447772.

The previous prime is 125171653. The next prime is 125171671. The reversal of 125171661 is 166171521.

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: 166171521 = 3 ⋅55390507.

It is not a de Polignac number, because 125171661 - 2³ = 125171653 is a prime.

It is a super-3 number, since 3×125171661³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125171621) 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, 20861941 + ... + 20861946.

It is an arithmetic number, because the mean of its divisors is an integer number (41723888).

Almost surely, 2^125171661 is an apocalyptic number.

It is an amenable number.

125171661 is a deficient number, since it is larger than the sum of its proper divisors (41723891).

125171661 is an equidigital number, since it uses as much as digits as its factorization.

125171661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41723890.

The product of its digits is 2520, while the sum is 30.

The square root of 125171661 is about 11188.0141669556. The cubic root of 125171661 is about 500.2287766399.

The spelling of 125171661 in words is "one hundred twenty-five million, one hundred seventy-one thousand, six hundred sixty-one".