125120421 has 24 divisors (see below), whose sum is σ = 186275544. Its totient is φ = 80870400.

The previous prime is 125120419. The next prime is 125120431. The reversal of 125120421 is 124021521.

125120421 is a `hidden beast` number, since 125 + 120 + 421 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 50211396 + 74909025 = 7086^2 + 8655^2 .

It is not a de Polignac number, because 125120421 - 2¹ = 125120419 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 125120394 and 125120403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125120431) 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 23 ways as a sum of consecutive naturals, for example, 133065 + ... + 134001.

It is an arithmetic number, because the mean of its divisors is an integer number (7761481).

Almost surely, 2^125120421 is an apocalyptic number.

It is an amenable number.

125120421 is a deficient number, since it is larger than the sum of its proper divisors (61155123).

125120421 is a wasteful number, since it uses less digits than its factorization.

125120421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381 (or 1378 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 125120421 is about 11185.7239819334. The cubic root of 125120421 is about 500.1605098010.

Adding to 125120421 its reverse (124021521), we get a palindrome (249141942).

The spelling of 125120421 in words is "one hundred twenty-five million, one hundred twenty thousand, four hundred twenty-one".