125163921 has 4 divisors (see below), whose sum is σ = 166885232. Its totient is φ = 83442612.

The previous prime is 125163919. The next prime is 125163923. The reversal of 125163921 is 129361521.

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: 129361521 = 3 ⋅43120507.

It is an interprime number because it is at equal distance from previous prime (125163919) and next prime (125163923).

It is not a de Polignac number, because 125163921 - 2¹ = 125163919 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (125163923) 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, 20860651 + ... + 20860656.

It is an arithmetic number, because the mean of its divisors is an integer number (41721308).

Almost surely, 2^125163921 is an apocalyptic number.

It is an amenable number.

125163921 is a deficient number, since it is larger than the sum of its proper divisors (41721311).

125163921 is an equidigital number, since it uses as much as digits as its factorization.

125163921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41721310.

The product of its digits is 3240, while the sum is 30.

The square root of 125163921 is about 11187.6682557180. The cubic root of 125163921 is about 500.2184658648.

The spelling of 125163921 in words is "one hundred twenty-five million, one hundred sixty-three thousand, nine hundred twenty-one".