125000081 has 4 divisors (see below), whose sum is σ = 125045232. Its totient is φ = 124954932.

The previous prime is 125000077. The next prime is 125000089. The reversal of 125000081 is 180000521.

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: 180000521 = 2203 ⋅81707.

It is a cyclic number.

It is not a de Polignac number, because 125000081 - 2² = 125000077 is a prime.

It is a super-2 number, since 2×125000081² = 31250040500013122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125000089) 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, 18131 + ... + 24056.

It is an arithmetic number, because the mean of its divisors is an integer number (31261308).

Almost surely, 2^125000081 is an apocalyptic number.

It is an amenable number.

125000081 is a deficient number, since it is larger than the sum of its proper divisors (45151).

125000081 is an equidigital number, since it uses as much as digits as its factorization.

125000081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45150.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 125000081 is about 11180.3435099285. The cubic root of 125000081 is about 500.0001080000. Note that the first 3 decimals are identical.

The spelling of 125000081 in words is "one hundred twenty-five million, eighty-one", and thus it is an aban number.