125220561 has 4 divisors (see below), whose sum is σ = 166960752. Its totient is φ = 83480372.

The previous prime is 125220559. The next prime is 125220577. The reversal of 125220561 is 165022521.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 125220561 - 2¹ = 125220559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (125220541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20870091 + ... + 20870096.

It is an arithmetic number, because the mean of its divisors is an integer number (41740188).

Almost surely, 2^125220561 is an apocalyptic number.

It is an amenable number.

125220561 is a deficient number, since it is larger than the sum of its proper divisors (41740191).

125220561 is an equidigital number, since it uses as much as digits as its factorization.

125220561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41740190.

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 125220561 is about 11190.1993279834. The cubic root of 125220561 is about 500.2939085350.

The spelling of 125220561 in words is "one hundred twenty-five million, two hundred twenty thousand, five hundred sixty-one".