125225021 has 4 divisors (see below), whose sum is σ = 125354172. Its totient is φ = 125095872.

The previous prime is 125225017. The next prime is 125225059. The reversal of 125225021 is 120522521.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 122899396 + 2325625 = 11086^2 + 1525^2 .

It is a cyclic number.

It is not a de Polignac number, because 125225021 - 2² = 125225017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 125224984 and 125225002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125225071) 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, 63110 + ... + 65063.

It is an arithmetic number, because the mean of its divisors is an integer number (31338543).

Almost surely, 2^125225021 is an apocalyptic number.

It is an amenable number.

125225021 is a deficient number, since it is larger than the sum of its proper divisors (129151).

125225021 is an equidigital number, since it uses as much as digits as its factorization.

125225021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129150.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 125225021 is about 11190.3986077351. The cubic root of 125225021 is about 500.2998481462.

Adding to 125225021 its reverse (120522521), we get a palindrome (245747542).

The spelling of 125225021 in words is "one hundred twenty-five million, two hundred twenty-five thousand, twenty-one".